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PRESENTS MADE TO THE ROYAL SOCIETY From Nov. 1776 to June 1777; WITH The NAMES of the DONORS. Donors. Presents. Omitted in the last Volume. John Reinhold Forster, LL.D. F.R.S. A large collection of Birds and Fishes, in Spirits, chiefly nonescripts, brought from the South Sea and the Cape of Good Hope. June 26. The Editor. The 54th Vol. of the Philosophical Transactions, printed at Wittenberg, 4° Mr. Valemont de Bomare. Mineralogie, ou exposition du regne mineral, 8° Society of Antiquaries. Prints published by them. Nov. 7. Sir W. Hamilton, K.B.F.R.S. Observations on the Volcanos of the Two Sicilies, 2 vols. fol. Mr. John Seiferth. Metallurgic Chemistry, 8° Forbernum Bergman, F.R.S. Commentationes Chemicæ, 4° Mr. Charles de Geer. Memoires pour servir à l'Histoire des Insectes, 4° Society of Physicians in London. Medical Observations and Enquiries, 8° Mr. Bernoulli, F.R.S. Recueil pour les Astronomes, 8° Ant. Maria Lorgna. Liste des Astronomes connus actuellement vivans, 8° Mr. D'Aprés de Mannevillette. Specimen de seriebus convergentibus, 4° Board of Longitude. Le Neptune Oriental, fol. Mr. Colombier. Nautical Almanack for 1778, 8° Preceptes sur la santé des gens de guerre, 8° Code de Medicine Militaire, 5 vols. 12° 1776. Donors. Nov. 7. Academy of Stockholm. Mr. Schaeffer, F.R.S. M. Jout. Mar. de Moyrie de Mayla, Mr. Bailly. L'Abbé Rozier. Mr. Morand. Mr. Dion du Séjour, F.R.S. Bequeathed by the late Dr. Maty. 24. Dr. Avenbrugger. Mr. de Lelyveld. Felice Fontana. Mr. Le Meunnier. J. Bernard. Mr. Geo. Atwood. Dec. 5. Mr. Bowyer. Mr. Nichols. 19th, Count de Salis, F.R.S. Mr. Wallott. Mr. J. H. de Magellan, F.R.S. 1777. Jan. 9. Mr. Bemetzrieder. Nic. Andria. Giamb. Beccaria. Presents. Swedish Transactions, No. 3, 4, of 1775, and No. 1, 2, of 1776. Abbildung des beständigen Elektricitätsträgers. Histoire Generale de la Chine. Histoire de l'Astronomie Ancienne. Journal de Physique, for Jan. Feb. March, April, May, June, 1776. Du Charbon de Terre, & des ses mines, fol. Essais sur les Phenomenes. Two Portraits, one of Descartes, the other of Fontenelle. Experimentum nascens de remedio specifico sub signo specifico in mania virorum. Essai sur les moyens de diminuer les dangers de la Mer. Nouvelle vue sur la proportion du coté d'un Quarré parfait avec sa diagonale. Ricerche Filosofiche sopra la fisica animale, tom. I. L'esprit des Usages & des coutumes des differens peuples, 3 vols. Several Medical Theses. Description of Experiments to illustrate a Course of Lectures. Dissertation on the Epistles of Phalaris. Supplement to Dr. Owen's Critica Sacra. An Appendix to the first Edition of the Origin of printing. A Version of the Psalms of David into the language of Engadine. Methode directe de demeler l'effet de la variation de l'obliquité de l'Eliptique. Dissertatio de monstris. Thesis Universa Philosophiae. Taité de Musique. Trattato delle acque Minerali. Della Ellettricita terrestre atmosferica a cielo sereno. Assemblee publique de la Société Royale des Sciences de Montpellier. Donors. Jan. 16. Board of Longitude. Dr. Cullen. 23. Prince Biscari. Mr. Henry Home. Felice Fontana. Royal Academy of Prussia. Feb. 6. The Archbishop of Canterbury. Mr. Leffallier. The Editor. March 6. L'Abbé Coyer, F. R. S. Mr. Donne. Cha. Pet. Layard, M. A. Court of Direct. of the E. I. Comp. 13. Mr. Gibelin. l'Abbé Rozier. 20. The Bishop of Oxford. Mr. George Forster, F. R. S. Dr. Wolf. Abb. Spallanzani. April 10. Board of Longitude. Mr. Lewis Lochee. Daniel Titio. Presents. Description of an engine for dividing Mathematical Instruments, First lines of the practice of Physick, Discorso Academico sopra un' antica Iscrizione, The Gentleman Farmer, Recherches Physiques sur l'air nitreux et sur l'air deplogistique, Recueil de Tables Astronomiques, A list of various Editions of the Bible, Vocabulaire des Termes de Marine, The 55th vol. of the Philosophical Trans- printed at Wittenberg, Idée Sommaire, ou vue generale du Systeme Physique et Metaphysique, 3 Vols of their Medical and Philosophical Commentaries, Commentaire sur le Code criminel d'Angle- terre, British Mariner's Assistant, Essay on Book-keeping, D° on Plane Geometry, D° on Vulgar and Decimal Arithmetick, A Sermon on the death of Dr. Maty, Experiences sur differentes especes d'air, Journal, de Physique, for July, August, Sept. Oct. Nov. Dec. 1776, The Life of William of Wykeham, An Account of a Voyage round the World, in 1772, 3 & 4, 2 vols. Many specimens of various Salts and Strata of the Salt Mines in Poland. Opusculi di Physica Animale, 2 vol. Nautical Almanack for 1779, System of Military Mathematicks, 2 vols. Essay on Military Education, Parus minimus Polonorum Remiz, Bononiensis Pendulinus, descriptus, Donors. 1777. 17. Rev. Dr. Priestley, F. R. S. Abbé Hondou. J. Miller. 24. Hugh Brown. Samuel Wegg, Esq. F. R. S. May 8. John Howard Esq. F. R. S. 15. Rev. Mr. Tooke. Captain Cook, F. R. S. 29. Board of Longitude. Mr. J. Chandler, F. R. S. June 12. Royal Academy of Sciences at Paris. Thomas Astle, Esq. F. R. S. 19. Berlin Academy. Mr. Bernoulli. Le Baron Hupfch. Mr. Cavallo. Presents. Experiments and observations on different kinds of Air, tom. III. 8° Six Mathematical Tracts, 8° Botanical Prints, N° XV. fol. True principles of Gunnery explained, 4° Meteorological Diary kept at York Fort, Hudson's Bay, fol. State of the prisons in England and Wales, 4° Pieces on Sculpture, and on the Statues of Peter the Great, 4° An Account of a Voyage round the World in 1772, 3 & 4. 2 vol. 4° Nautical Almanack for 1780, 8° Meteorological Diary, fol. Connoissance des Temps, pour l'année 1778, 8° A Catalogue of the MSS. in the Cottonian Library, 8° Nouveaux Memoires. Année 1774, 4° Nouvelles Literaires de divers pays, 8° Relation de la découverte d'un remede efficace contre la maladie contagieuse des bêtes à cornes, 6 copies, 8° A Treatise on Electricity, 8° AN INDEX TO THE SIXTY-SEVENTH VOLUME OF THE PHILOSOPHICAL TRANSACTIONS. A. Abscesses, an account of a hard substance extracted from one, in a woman's groin, p. 461—463. The substance caused by a peg of wood which she had swallowed sixteen years before, p. 462, n. Ackbar, the emperor, said to have built an observatory at Benares, p. 604. An account of it, p. 598—607. Adriatic, an account of its tides, p. 145—161. Ether, degree of cold produced by its evaporation under the receiver of an air-pump whilst exhausting, p. 646—648. Africa, an account of a journey into Africa from the Cape of Good-Hope, and a description of a new species of cuckow, p. 38. Journey undertaken in August 1775, ibid. Season so exceeding dry that the inhabitants quitted their country-seats, p. 39. Cattle perished for want of grass and water, ibid. Vegetables of all kinds burnt up, ibid. Animals met with and hunted on the journey, p. 39, 40. See Sparman, Cuckow. Air, in what manner it may be affected by rain, p. 244. An active solvent of water, in proportion to its dryness, p. 245, 257. Water may exist in air in three states, p. 257. Remarks on these different states of water existing in air, p. 257—259. Concerning air in mines, p. 412. A comparative view of the temperature of the air at Liverpool during the years 1772, 1773, 1774, and 1775, p. 247—250. Relative weight of air and water, p. 560. Expansions of common air do not keep pace with the dilatations. dilatations of quicksilver, p. 695. Elastic force of moist air superior to that of dry, p. 705. Concerning the elastic force of air, p. 748, 749-753, 754. An experiment to determine hydrostatically the specific gravities of air and quicksilver, with a given temperature and pressure, and remarks thereon, p. 557-570. Experiments on the expansion of air in the manometer, p. 689-696. Thermometrical spaces compared with those of the manometer, p. 697. Experiments for determining the actual expansion of common air in the manometer affected by the heat of 212°, p. 698-715. Air-pump, an account of some experiments made with one, on Mr. Smeaton's principle; together with some experiments with a common air-pump, p. 614. Description of Mr. Smeaton's pear-gage, p. 614-616. Air in the pump expanded 4000 times, p. 617. Enquiry from whence this great superiority of expansion could proceed, p. 617. Disagreement between the pear-gage and the other gages, p. 618, 622. Disagreement accounted for, p. 622-644. Experiment in which the apparatus was made as free from moisture as possible, p. 624. Near agreement between the pear-gage and the barometer, p. 625. To discover whether a vapour from moisture might not be contained in the substances used, p. 625-627. Elastic vapours arose from the leather and box-wood used, and influenced the barometer-gages, p. 627. Pear-gage not affected by the vapour, ibid. Experiments on leather, alum, oil, and tallow, to find from which the vapour chiefly arose, p. 628. Arose principally from the leather, ibid. To determine that the moisture in the leather gave the vapour, p. 629, 630. The effect of vapour arising from small quantities of fluids, and from some substances, p. 630, 631. Wet leather, used to connect the receiver and plate, prevents the pump from exhausting to any considerable degree, p. 632. Different degrees of heat affect exhaustion, p. 633. Comparative excellency between the pump on Mr. Smeaton's principle, and a common one, p. 633, 634. The effect of water used in the barrels of pumps to make the pistons move air tight in them, p. 634, 635. Remarks concerning Mr. Smeaton's pump not exhausting to as great a degree as the pump here used, p. 635-637. Further experiments made with the same air-pump, the result of which were different from the former, p. 637-646. Degree of cold produced by the evaporation of ether under a receiver whilst exhausting, 646-648. Alps. An account of Mont Saleve, p. 515, n. 527. An account of the Mole, p. 533-539. Barometrical observations to ascertain the heights of the Alps, p. 513, &c. Alte Segen, a mine in the Hartz, its height determined by barometrical observations, p. 421, 422, 441-443. Altitudes determined by the barometer, 515-532, 530-546, 549, 550, 552-554, 592-597. Rule for measuring such heights, p. 683, 687, 734, 735, 757, 758, 762, 763, n. The rule which answers in middle latitudes will not in the frigid and torrid torrid zones, p. 742—756. Remarks on the error of the rule in the tables of computation, and a method of bringing the theory of the barometer to greater perfection, p. 759—770. Precepts and tables for making the calculations, p. 571—591. Computations of barometrical observations made on various heights, p. 773—787. Anemonies. See Sea anemonies. Angles. An account of a new instrument for measuring small angles, called the prismatic micrometer, p. 799. See Micrometer. Antelopes, an animal of that sort, frequently hunted in Africa, p. 40. Apparatus. Description of one for further illustrating the Franklinian theory of the Leyden bottle, p. 99, 100. A simple electrical apparatus, by which almost every article may be examined with the utmost facility, p. 118. Observations and precautions in the use of it, p. 119, 120. The electricity of various substances discovered with it, p. 122—126. Remark on the rubbers used, p. 127—129. Apparatus for determining the annual evaporation in Liverpool, p. 245, 246. Apples. Method of raising pine-apples in water, p. 649—652. Arabic. A translation of a passage in Ebn Younes; with some remarks thereon, p. 231. See Ebn Younes. Arcs. Computations of the lengths of circular arcs by means of infinite series, derived from their tangents, p. 194—199. Computations of an arch of thirty degrees, p. 199—203. Computation of an arch of forty-five degrees, p. 203—215. Computation of the series which expresses the time of the descent of a pendulum through the arch of a circle, p. 215—230. Articles (mathematical) leading to a clear and satisfactory consideration of the motion of the earth's axis, p. 267—288. How the joint centrifugal force of the particles of a spheroid or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. Astronomy, the ancient Brahmins had a knowledge of it, p. 598. 601—606. Atmosphere, observations on its electricity, p. 50. A quantity of electricity in the atmosphere at all times, ibid. The electricity of the atmosphere, and of fogs of the same kind, ibid. Evaporation considered as a test of the moisture or dryness of the atmosphere, p. 244. See Evaporation. Atmosphere of Peru constantly obscured with vapours during part of the year, and the whole country involved in thick fogs, p. 257, 258. Depth of rain not a true index of the moisture or dryness of the atmosphere, p. 250—252. Why much rain gives no more moisture to it than a little, p. 251. Atmosphere amazingly clear in the East Indies, p. 604. Atmospherical electrometer, description and use of one, p. 48, 49. Aubert, (Alexander, Esq;) his attestation concerning Dr. Maskelyne's invention of the prismatic micrometer, p. 815. Axis, the earth's, mathematical articles leading to a clear and satisfactory consideration of its motion, p. 267—288. How the joint centrifugal force of the particles of a spheroid... spheroid or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. B. Barker (Sir Robert) his account of the Bramins' observatory at Benares, p. 598. See Bramins' Observatory. Barker (Thomas, Esq;) an extract of his register of the barometer, thermometer, and rain, at Lyndon, in Rutland, for the year 1776, p. 350. See Lyndon. Barometer. Experiments and observations made in Britain, in order to obtain a rule for measuring heights with a barometer, p. 653. Mr. De Luc the most successful in measuring vertical heights with the barometer, p. 654, 655. Rule deduced from his observations on Saleve, p. 655, 656. Expansion of quicksilver in the tubes of his barometers resulting from the Saleve observations, p. 656—658. Description of the barometer with which Col. Roy's experiments were made, p. 658, 659. Experiments on the expansion of quicksilver, p. 659—681. Rate of expansion of a column of quicksilver in the tube of a barometer, p. 682. Construction and application of a table of equation for the expansion of quicksilver in the tubes of barometers, p. 683—686. The equation to be applied to the observed height of quicksilver in the barometer, from 15 to 31 inches; and for differences of temperature extending to 102° of Fahrenheit; whereby the column is reduced to the height it would have stood at in the temperature of 32°, p. 687. Experiments on the expansion of air in the manometer, p. 689—696. Thermometrical spaces compared with those of the manometer, p. 697. Experiments for determining the actual expansion of common air in the manometer affected by the heat of 212°, p. 698—715. An account of barometrical observations made in Britain, wherein they are compared with some others of the same kind made in distant countries, p. 715—749. Principles on which the table of equation for the heat of air was constructed, p. 749—759. Remarks on the error of the rule in the tables of computation, and a method of bringing the theory of the barometer to greater perfection, p. 759—770. The equation depending on the temperature of the column of air, and its elevation above the sea, as denoted by the mean height of mercury in the inferior and superior barometers, p. 771. Computations of barometrical observations made on heights in and near London, p. 773. Computations of those made on heights near Taybridge in Perthshire; and of those near Lanark, p. 775. Computations of those made on heights near Linhouse; and of those near Carnarvon in North Wales, p. 779. Computations of part of Mr. De Luc's barometrical observations, answering to the coldest and hottest temperatures of the air, p. 771—784. Mr. De la Caille's barometrical observations at the Cape of Good-hope, p. 784. Computations of barometrical observations made on heights that have not been determined geometrically, p. 785. Computations of Mr. Bouguer's observations in Peru, p. 787. Barometer, state of it at Lyndon, in Rutland, during the year 1776, p. 350. At Bristol, p. 353. At London, for each month throughout the same year, p. 358—361. Greatest, least, and mean height, in each month, p. 382. Heights determined by barometrical observations. See Heights. Description of a portable barometer, p. 658, 659. Effect of winds on the barometer, p. 751—753. Fixing the scale of barometers with cisterns recommended, p. 405, 406. Observations made in Savoy, in order to ascertain the height of mountains by means of the barometer; being an examination of Mr. De Luc's rules, delivered in his Recherches sur les Modifications de l'Atmosphere, p. 513. See Mountains. Rule for measuring heights with the barometer, p. 686, 687, 734, 735, 757, 758, 762, 763, n. The rule which answers in middle latitudes, will not in the frigid and torrid zones, p. 742—756. Barometer tubes dilate much more than solid glass rods, p. 663, 664. Barometrical observations on the depth of the mines in the Hartz, p. 401. Corresponding observations taken, p. 405, 428, 429. Observations in places where the height is ascertained, p. 408—424. In the Dorothea, the Caroline, and the Benedict, in the environs of Clausthal, p. 408—412. In the Kaunkuhl, at the Ramelsburg near Goslar, p. 417—419. At Alte Seegen, in the valley of Bremeke, p. 421, 422. Near Lasfelde, in the valley of Osterode, ibid. The subterraneous geometer's method of finding the depths of mines, p. 423, 424. Observations determining the height of some points of the Hartz, not verified by geometrical survey, p. 425—429. The height of the Brocken above Oder-brucke, p. 429. That of Oder-brucke above Clausthal, ibid. That of Clausthal above Gottingen, ibid. And that of Gottingen above Hanover, ibid. Elevation of the Brocken above Hanover, ibid. Remark on these observations, p. 430. A detail and calculations of barometrical observations made at the Hartz, in October 1776, p. 431—449. Observations on the mines of Clausthal, p. 431—435. At the Ramelsberg, p. 436—440. Observations at two points geometrically determined on the outside of the mountain, relatively to the mine of Alte Seegen, p. 441—443. Observations to determine the height of the Brocken, with respect to Gottingen and Hanover, p. 444—449.—Barometrical observations made in Savoy, to ascertain the heights of mountains, p. 513, &c. Precepts and tables for making these barometrical calculations, p. 571—597. Basilard, (William, Esq;) on the culture of pine-apples, p. 649. See Pine-apples. Beasts of prey, frequently seen in Africa, p. 39, 40. Beech-trees. The flourishing state of one that had been frequently washed and rubbed, compared to others of the same nature, p. 12—14. Bees, wild, how men are conducted to them by the Honey-Guide, a curious species of cuckow, p. 43—45. See Cuckow. Bees, discoveries on the sex of them, explaining the manner in which their species is propagated; with an account of the utility that may be derived from those discoveries by the actual application of them to practice, p. 15. Mode of propagating their species species yet undiscovered, p. 15, 16. Never detected in the act of copulation, p. 16, 18. Their fecundation is by an impregnation from the males, p. 17, 18, 20. Drones have some resemblances to the male organs of generation, p. 18. The different sexes that constitute the republic of bees, p. 19. Concerning the sex of the working-bees, p. 19, 20. Drones discovered as small as common bees, p. 21, 25. Drones well furnished with seminal liquor, and fecundating organs, p. 22. Naturalists who reject the use of drones in the propagation of bees had no knowledge of those small ones, ibid. An experiment proving that the eggs of the queen-bee are fecundated by the males, p. 22, 23. How they are impregnated, ibid. Another experiment in proof thereof, p. 24, 25. Drones have no sting, p. 25, 26. A third experiment, in which the swarm was entirely cleared of the males, and in which the eggs of the queen-bee produced nothing, p. 26. Bees all quit their hive on being disappointed of their young, ibid. They attempt to enter the hive of another swarm, and the queen is slain in the engagement, p. 26, 27. The great desire of perpetuating their species probably induces them to go to the other hive in search of males, p. 27. A fourth experiment, shewing that the male-bees must impregnate the eggs to produce young ones, p. 27, 28. Queen-bees produced from the common eggs, p. 28—30. The working-bees have the power of making a queen of any worm in the hive, p. 30, 31. The received opinion that the queen-bees are produced from a particular kind of egg, erroneous, p. 31. What advantages may accrue to the public from these observations, p. 31, 32. Benares, an account of the Bramins observatory there, p. 598. See Bramins' Observatory. Benedict, a mine in the Hartz; its depth determined by barometrical observations, p. 408—412, 435. Bengal, governor of, grants a peace to the Boutaners, p. 468. Enters into a treaty of commerce with them, p. 469. Translation of the letter he received from the Taythoo Lama, p. 489—492. Bison. The North American Bison, the same as the great buffaloe in the Wilds of Africa, p. 40. Bodies. A new theory of the rotatory motion of bodies affected by forces disturbing such motion, p. 269—295. Singular method of bestowing dead-bodies among the Thibetians, p. 478. Bogle (Mr.) sent to the court of Thibet, to negotiate a treaty of commerce with the Boutaners, p. 469. His description of their country, &c. p. 469—472. And character of the Taythoo Lama, p. 479. Boiling point, experiments to determine it in thermometers, p. 818—833. Rules to be observed in adjusting the boiling point of thermometers, p. 845—855. Boscovich, Abbé, his account of a new micrometer and megameter, p. 789—798, 812—815. Bottle, Leyden, Dr. Franklin's theory of it further illustrated, p. 100, &c. Bouguer, Mr. Computation of his barometrical observations in Peru, p. 787. Boutan, the kingdom of Thibet so called, p. 466. An account of it, p. 465, &c. Boutaners, [an account of their first meeting with the Europeans at the attack of Cooch Behar, p. 467, Their great surprize at each other, p. 467, 468. The Boutaners, conquered by the Europeans, sue for peace, p. 468. Boxwood, its effect in experiments with the air-pump, p. 626. Bramins' Observatory, at Benares, an account of it, p. 598. Ancient Bramins had a knowledge of astronomy, 598. 604—606. A number of curious instruments in their observatory in the greatest preservation, p. 599. Said to have been erected two hundred years ago, ibid. The construction and situation of these instruments, p. 599—601. Description and use of them, p. 601—604. 607. This Observatory said to have been built by the emperor Ackbar, p. 604. Bristol, an extract of a meteorological journal kept there for the year 1776, p. 353. See Meteorological Journal. Britain. Experiments and observations made in Britain, in order to obtain a rule for measuring heights with the barometer, p. 653. See Barometer. Brocken in the Hartz, its height above Hanover determined by barometrical observations, p. 429. 444—449. Brownrigg, Dr. his observation on the evaporation of some parts of England, p. 253. Not correspondent with that at Liverpool, ibid. Buffaloes, great ones in the wilds of Africa, p. 40. The same as the North Americans: Bifon, ibid. Buildings. Some account of the Thibetian buildings, p. 479. C. Cabbage bark tree of Jamaica, its description and use, p. 507—512. Canton's electrometer. Experiments with Mr. Hemming's electrical cylinder some days after using it, on the balls of Canton's electrometer, p. 109—113. New electrical experiments and observations; with an improvement of Mr. Canton's electrometer, p. 388. See Electrical experiments. Cape of Good-Hope, an account of a journey from thence into Africa, and a description of a new species of cuckow, p. 38. See African Cuckow. Mr. De la Caille's barometrical observations there, p. 784. Cards, painted with different water-colours, electrical experiments on them, p. 392—394. Caribbees. Description of the Jesuits Bark tree of the Caribbees, p. 504—506. Garnarvon. Computations of barometrical observations made on heights near, p. 779. Caroline, a mine in the Hartz, its depth determined by barometrical observations, p. 408—412. 434. Case of the fasting woman in Rossshire, p. 1—11. Cat. A coated phial may be charged with electrical sparks from the back of a cat, strong enough to pierce a hole through a card with its discharge, p. 396. A species of pole-cat (Viverra Putorius), found in Africa, p. 40. Cavallo, Mr. Tiberius, his account of some new electrical experiments, p. 48. See Electrical experiments. His experiments and observations on Mr. Volta's electrical machine, p. 116—118. His new electrical experiments and observations; with an improvement of Mr. Canton's electrometer, p. 388. See Electrical experiments. Cavendish, Mr. accounts for a disagreement between the pear-gage and the other gages in an air-pump, p. 622—624. Chocolate, on its electricity; and the restoration of that property to it, when lost, by melting it together with a small quantity of olive-oil, p. 94—97. Cisterns. Fixing the scale of barometers with cisterns, recommended, p. 405, 406. Clausthal, in the Hartz, depth of some mines there determined by barometrical observations, p. 408—412. 431—435. Its height above Gottingen determined by the barometer, p. 429. 444—449. Clock. A pendulum-rod of solid glass dilates much less than a steel one, p. 698, 699. Coated phial may be charged with electrical sparks strong enough to pierce a hole through a card with its discharge, from a piece of new flannel, a hare's skin, or a piece of paper, p. 396. Colours. An account of persons who could not distinguish colours, p. 260.—Harris, who had otherwise a good sight, discovered a want of the idea of colours at four years of age, p. 261. Why he might not observe this defect earlier, ibid. Could not discern the difference of colour in cherries, p. 262. He could only guess the name of any colour, except distinguishing white from black, or black from any light or bright colour, p. 262, 263. He could distinguish a striped ribbon from a plain one, but could not tell the colours, p. 262. Was very desirous of understanding the nature of light and colours, p. 263. He had two brothers, who likewise had no idea of colours, ibid. Account of one of them, p. 263—265. Colours. Electrical Experiments on water-colours, p. 392—394. On oil-colours, p. 394, 395. Committee. The report of the committee appointed by the Royal Society to consider of the best method of adjusting the fixed points of thermometers; and of the precautions necessary to be used in making experiments with those instruments, p. 816. See Thermometers. Cooch Behar. Europeans and Boutsaners first met at its attack, p. 467. Their great surprize at each other, p. 467, 468. Boutsaners, conquered by the Europeans, sue for peace, p. 468. Copernicus, an account of a portrait of him, presented to the Royal Society by Dr. Wolf, p. 33. Copied from an original in the possession of Mr. Huszarzewski, p. 33, 34. A portrait of him in the great church at Thorn, p. 34. Compared with Mr. Huszarzewski's, farzewski's, p. 34, 35. The latter is at least 150 years old, ibid. History of this portrait, p. 36, 37. Great likeness between the copy and original, p. 37. Copulation, bees never detected in that act, p. 16, 18. Coftard, Rev. Mr. George, his translation of a passage in Ebn Younes; with some remarks thereon, p. 231. See Ebn Younes. Cow, the Thibetians hold it in great veneration, p. 478. Cow-tails, remarkable ones produced in the kingdom of Thibet, p. 484. Their use, p. 484, 485. Description of the beast, p. 484. Creek Fairrick, or Peter's Rock, a volcanic-hill near Inverness, an account of it, p. 385—387. Crucius, his observation on the exhalation of water at Delft in Holland, p. 252. Cuckow, Honey-guide, or Cuculus Indicator, a curious species of cuckow in the interior parts of Africa, p. 43. Smaller than the European cuckow, ibid. Men and beasts are conducted to wild bee-hives by this bird, ibid. Its motive and method of discovering the bee-hives to men, p. 43—45. Accused of sometimes conducting its followers to wild beasts and venomous serpents, p. 45. Description of the Honey-guide's nest; p. 45, 46. Descriptio cuculi indicatoris, p. 46, 47. Cuculus Indicator, or Honey-Guide, a curious species of cuckow in the interior parts of Africa, p. 43. See Cuckow. Cylinder. Experiments with Mr. Hemming's electrical cylinder, for some days after using it, on the balls of Canton's electrometer, p. 109—113. Cylinder or spheroid. How the joint centrifugal force of the particles of a spheroid or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. D. Davenport, Ann, her remarkable case, p. 458. Miserable state of the patient, p. 459, 460. An abscess in her groin opened, p. 460. A second formed, and opened, ibid. Several holes in her belly caused by a mortification, p. 461. A third abscess formed, which was left to open of itself, ibid. A hard substance extracted therefrom, p. 462. An account of the extraction, p. 462, 463. The substance taken from her caused by a peg of wood which she had swallowed fifteen years before, p. 462, n. Patient in a fair way of recovery, p. 463. The minister's certificate of the truth of the case, p. 464. Days. Number of fair and frothy days in Bristol in the year 1776, p. 354. Dead bodies, a singular method of bestowing them among the Thibetians, p. 478. Debraw, Mr. John, his discoveries in the sex of bees, explaining the manner in which their species is propagated; with an account of the utility that may be derived from those discoveries by the actual application of them to practice, p. 15. See Bees. Deer. Musk-deer common in the mountains of Thibet, p. 485, 486. De la Caille, Mr. his barometrical observations at the Cape of Good Hope, p. 784. Delai Lama, a description of his country, p. 469—471. He is the great object of adoration of the heathen Tartars, p. 474—476. Delft, in Holland, observation on the exhalation from waters there, p. 252. De Luc, Mr. John Andrew, his barometrical observations on the depths of the mines in the Hartz, p. 401. See Barometrical observations. On the expansion of quicksilver in the tubes of barometers, p. 683, 684. Concerning his barometrical observations on Saleve, p. 715, 716—729, &c. Mr. De Luc the most successful in measuring vertical heights with the barometer, p. 654, 655. Rule deduced from his observations on Saleve, p. 655, 656. Expansion of quicksilver in the tubes of his barometers resulting from the Saleve observations, p. 656—658. Computations of part of his barometrical observations, answering to the coldest and hottest temperatures of the air, p. 781—784. His method of adjusting the boiling point of the thermometer, p. 832. An examination of the rules delivered in his Recherches sur les Modifications de l'Atmosphere, by observations made in Savoy, in order to ascertain the height of mountains by means of the barometer, p. 513. See Mountains. Depths of mines, measured by the barometer, p. 401—409. The subterraneous geometer's method of finding these depths, p. 423, 424. Precepts and tables for calculating any accessible heights or depths from barometrical observations, p. 571—591. De Saussure, Mr. his barometrical observations to ascertain the height of the Mole, p. 549, 550. Diameters. The ratio of the diameters of the earth, p. 767. Dicquemare, the Abbé, his third essay on sea-anemonies, p. 56. See Sea-anemonies. Dobson, Dr. his observations on the annual evaporation at Liverpool; and on evaporation considered as a test of the moisture or dryness of the atmosphere, p. 244. See Evaporation. Dollond, Mr. his letter concerning Dr. Maskelyne's invention of the prismatic micrometer, p. 813—815. Dorothea, a mine in the Hartz, its depth determined by barometrical observations, p. 408—412. 431—435. Drink. An account of a woman living without food or drink, p. 1. See Woman. Drones have some resemblances to the male organs of generation, p. 18. Drones as small as common bees, p. 21, 25. Drones well furnished with seminal liquor, and fecundating organs, p. 22, 25. They have a share in the propagation of bees, p. 22—28. Drones have no sting, p. 25, 26. Dryness or moisture of the atmosphere; evaporation considered as a test of it, p. 244. See Evaporation. E. Earth. Annual evaporation from the earth, only a sixth part of what it is from water, p. 253. The exhalation from the earth is about a fifth part of what descends in rain, p. 254. Some mathematical articles leading to a clear and satisfactory consideration of of the motion of the earth's axis, p. 267—288. How the joint centrifugal force of the particles of a spheroid or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. The ratio of the earth's diameters, p. 767. Best method of determining the figure of the earth, ibid. East Indies. The atmosphere amazingly clear there, p. 604. Ebn Younes. Translation of a passage in Ebn Younes; with some remarks thereon, p. 231. Numbers in the manuscript supposed to be different from what they were in the original tables, ibid. A mistake in the Arabic letters and figures easily made by a person ignorant of his subject, p. 232. An instance of this sort, ibid. Differences in the manuscript observations, and the calculations by modern tables accounted for, p. 232—240. A translation of the Arabic passage entire, p. 240—243. Eclipses of Jupiter's first satellites, observed during the last ten years, relatively to the difference of longitude at Paris and Greenwich resulting therefrom; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories, p. 162—186. Edinburgh, computations of barometrical observations made on heights near there, p. 777. Electrical Experiments, an account of some new ones, p. 48. Description and use of the atmospherical electrometer, p. 48, 49. Part of a journal of observations on the electricity of the atmosphere, p. 50. A quantity of electricity is at all times in the atmosphere, ibid. The electricity of the atmosphere or fogs is always of the same kind, ibid. The strongest electricity is in thick fogs; the weakest in cloudy weather, ibid. Description of the electrometer for the rain, p. 51, 52. Experiments made with a glass-tube hermetically sealed, and having some quicksilver inclosed in its cavity, p. 53—55. New electrical experiments and observations, with an improvement of Mr. Canton's electrometer, p. 388. The glass plate used in the following experiments coated with sealing-wax, ibid. Experiments on Mr. Volta's plates, commonly called a machine for exhibiting perpetual electricity, p. 389—392. Experiments on watercolours, p. 392—394. On oil colours, p. 394, 395. Promiscuous experiments, p. 396, 397. On a piece of new white flannel, tied round the globe of an electrical machine, p. 397, 398. On a phial, the inside coating of which was stuck with varnish, p. 398, 399. Description of a pocket electrometer, p. 399, 400. Electrical machine, experiments and observations on Mr. Volta's, p. 116—118. Experiments on his machine for exhibiting perpetual electricity, p. 389—392. Electrical cylinder (Mr. Hemming's), experiments with it on the balls of Canton's electrometer, some days after using it, p. 109—113. Electricity. Experiments and observations in Electricity, p. 85. Remarks on the effects of lamp-black and tar, or lamp-black and oil, as protectors of bodies from the stroke of lightning, p. 85—89. Similar effects produced by experiments in the artificial cial electricity, p. 89—91. Corollaries deduced from the above experiments and observations, p. 91—94. On the electricity of chocolate, 94—96. The restoration of that property to it, when lost, by melting it together with a small quantity of olive-oil, p. 96, 97. Remarks on electricity, 97, 98. Observations on some new and singular phenomena in excited and charged glasses; with experiments made in consequence of these phenomena, farther illustrating the Franklinian theory of the Leyden bottle, p. 98—116. A description of the apparatus constructed for that purpose by Mr. Henly, p. 99, 100. Experiments and observations on Mr. Volta’s machine, with remarks, p. 116—118. A simple electrical apparatus, by which almost every article may be examined with the utmost facility, p. 118. Observations and precautions in the use of it, p. 119, 120. The electricity of various substances discovered with it, p. 122. Metals, ibid. Animal substances, p. 123. Vegetables, p. 124, 125. Corallines, p. 125. Salts, ibid. Fossil and mineral substances, p. 125, 126. Artificial substances, p. 126. Remark on the rubbers used, p. 127—129. Thoughts on the action, influence, and effects of electricity, p. 129—144. Observations on the electricity of the atmosphere, p. 50. A quantity of electricity in the atmosphere at all times, ibid. The electricity of the atmosphere and fogs of the same kind, ibid. Strongest electricity is in thick fogs; the weakest in cloudy weather, ibid. Electricity may be obtained by rubbing smooth glass with a rabbit’s skin, p. 397. Electrometer, an atmospherical one, its description and use, p. 48, 49. Description of one for the rain, p. 51, 52. Description of a pocket one, p. 399, 400. Mr. Hemming’s experiments with his electrical cylinder; some days after using it, on the balls of Canton’s electrometer, p. 109—113. Emelman, Mr. his journey into Africa from the Cape of Good Hope, p. 38. See Africa. England, the evaporation of some parts of it, p. 253. Not correspondent with that at Liverpool, ibid. Evaporation. Observations on the annual evaporation at Liverpool; and on evaporation considered as a test of the moisture or dryness of the atmosphere, p. 244. Quantity of rain falling not so good a test of the state of the atmosphere as evaporation, p. 244—245. Method of determining the annual evaporation in Liverpool, p. 245, 246. Explanation of the tables of evaporation, p. 246. A comparative view of the evaporation, rain, winds, and temperature of the air there, during the years 1772, 1773, 1774, and 1775, p. 247—250. Depth of rain not a true index of the moisture or dryness of the atmosphere, p. 250—252. Why much rain gives no more moisture to the atmosphere than a little, p. 251. Annual evaporation at Liverpool, p. 252. Evaporation at London, p. 252. Annual evaporation at London exceeds that at Liverpool, ibid. Exhalation from water at Delft in Holland, ibid. Evaporation of some parts of England, p. 253. Not correspondent with that at Liverpool, ibid. Annual evaporation from water six times as much as from the earth, ibid. More falls in rain rain than is raised in vapour, supposing the whole a surface of water, p. 254. The exhalation from the earth is about a sixth part of what descends in rain, ibid. How the rain is collected and restored to the sources from whence it came, p. 254, 255. Annual fall of rain between Lancashire and Yorkshire, p. 255. Exceeds that at Liverpool, ibid. An experiment to ascertain whether the fact of evaporation, going on equally well in an exhausted receiver, was not an unsurmountable objection to that theory concerning evaporation which supposes a chemical solution of water in air, p. 256. Air is a chemical solvent of water, and a cause of its evaporation, p. 257. Heat is another cause of the evaporation of water, ibid. Water may exist in air in three states, ibid. Remarks on these different states of water existing in air, p. 257—259. The degree of cold produced by the evaporation of æther under the receiver of an air-pump whilst exhausting, p. 646—648. Euclid, almost all the geometrical reasonings of mathematicians are derived from him, p. 450. Evelyn, Mr. his advice of rubbing the stems of trees to increase their growth, put in practice, p. 12. The design answered, p. 12—14. Europeans, an account of their first meeting with the Bouteners, at the attack of Cooch Behar, p. 467. Their great surprize at each other, p. 467, 468. Boutaners, conquered by the Europeans, sue for peace, p. 468. Exhalation. See Evaporation. Expansion of quicksilver in the tubes of Mr. De Luc's barometer, resulting from the Salve observations, p. 656—658. Experiments on the expansion of quicksilver, p. 659—681. Rate of expansion of a column of quicksilver in the tube of a barometer, p. 682. Construction and application of a table of equation, for the expansion of quicksilver in the tubes of barometers, p. 683—686. Experiments on the expansion of air in the manometer, p. 689—696. Thermometrical spaces compared with those of the manometer, p. 697. Experiments for determining the actual expansion of common air in the manometer, affected by the heat of 212°, p. 698—715. Expansion of the glass tube and the scale of the thermometers, their difference, p. 834. Experiments, proving that the eggs of the queen-bee are fecundated by the males, p. 22—28. Electrical experiments, p. 48—55. 85—144. 388—400. Barometrical experiments, p. 401—449. 515—569. Experiments made with an air-pump, p. 614—648. Experiments to obtain a rule for measuring heights with the barometer, p. 653—788. Experiments to determine the boiling points of thermometers, p. 818—833. F. Fair. The number of fair and frosty days in Bristol in the year 1776, p. 354. Farr, Dr. Samuel. Extract of his meteorological journal for the year 1776, kept at Bristol, p. 353. See Meteorological Journal. Fasting woman, an account of her, p. 1—11. Flannel. A coated phial may be charged with electrical sparks from a piece of new flannel, sufficiently to pierce a hole through a card with its discharge, p. 396. New flannel rubbed against glass will sometimes make it electric, p. 397. An experiment with a piece of dry or warm flannel tied round the globe of an electrical machine, 397, 398. Fogs, contain the same kind of electricity as the atmosphere, p. 50. Thick fogs contain the strongest electricity, ibid. The whole country of Peru involved in thick fogs during part of the year, p. 258. Food. An account of a woman living without food or drink, p. 1. See Woman. Franklin, Dr. his theory of the Leyden-bottle, further illustrated, p. 100. &c. Freezing point, concerning adjusting it in the thermometers, p. 856, 857. Frosty and fair days in Bristol in the year 1776, their number, p. 354. Fynney, Mr. Fielding Best, his account of the case of Ann Davenport, p. 458. See Davenport. G. Ganges, its waters held in great veneration by the Thibetians, p. 478. Garuai, (thick fogs) the whole country of Peru involved in them during part of the year, p. 258. Generation. Some resemblance of the male organs of generation in drones, p. 18. Geometer. The subterraneous geometer's method of finding the depths of mines in the Hartz, p. 423, 424. Geometers, almost all their reasonings derived from Euclid, p. 450. Their reasonings with respect to proportional magnitudes very confined, p. 450, 451. An investigation concerning it, p. 451—457. Germany, barometrical observations on the depth of several mines there, p. 401. See Barometrical observations. Glass. Observations on some new and singular phenomena in excited and charged glass; with experiments made in consequence thereof, further illustrating the Franklinian theory of the Leyden-bottle, p. 98—116. Smooth glass rubbed with a rabbit's skin acquires electricity, p. 397. Will sometimes become electric when rubbed with new flannel, ibid. Solid glass-rods dilate much less than barometer tubes, p. 663, 664. A solid glass pendulum-rod dilates much less than a steel-one, p. 698, 699. Glass plates in electrical experiments, sealing-wax the best coating for them, p. 389, n. Glass tube hermetically sealed, and having some quicksilver inclosed in its cavity, experiments made with one, p. 53—55. The difference of expansion of the glass tube and the scale of thermometers, p. 834. Glazie, Mr. James, his general mathematical laws, which regulate and extend proportion universally; or, a method of comparing magnitudes of any kind together, in all the possible degrees of increase and decrease, p. 450—457. Gold, Gold, great quantities found in the kingdom of Thibet, p. 486, 487. Good Hope, Cape of, Mr. De la Caille's barometrical observations there, p. 784. Gottingen in the Hartz, its height above Hanover determined by barometrical observations, p. 429, 444—449. Gravities. An experiment to determine hydrostatically the specific gravities of air and quicksilver, with a given temperature and pressure; and remarks thereon, p. 557—570. Great River, in the kingdom of Thibet, some account of it, p. 481, 482. Great quantities of gold found in its sands, p. 486. Greenwich and Paris, concerning the difference of longitude there, resulting from the eclipses of Jupiter's first satellites, observed during the last ten years; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories, p. 162—186. Groin. An account of a hard substance extracted from a woman's groin, p. 461—463. Caused by swallowing a peg of wood sixteen years before, p. 462. Groot Vaader's Bosch, a wood in the interior part of Africa, a curious species of cuckow there, p. 43. See Cuckow. Growth of trees, increased by washing and rubbing, p. 12—14. H. Hadley, Mr. remarks on the defects in his method of polishing the speculum for reflecting telescopes, p. 318—320. A more perfect method of polishing and giving a correct parabolic figure to the metal at the same time, p. 327—335. Hales, Dr. his advice of washing the stems of trees to increase their growth, put in practice, p. 12. The design answered, p. 12—14. Dr. Hale's calculation of the annual evaporation in England, p. 253. Halley, Dr. his observations on the exhalation of water in London, p. 252. Hanover. The heights of Gottingen, Clausthal, Oder-brucke, and Brocken, above Hanover, determined by barometrical observations, p. 429, 444—449. Hare's skin, a coated phial may be charged with electrical sparks from one, sufficiently to pierce a hole through a card with its discharge, p. 396. Harris, Mr. an account of him and his two brothers, neither of whom could distinguish colours, p. 260—265. Hartz, barometrical observations on the depths of mines there, p. 401. See Barometrical observations. Hastings, Mr. governor of Bengal, grants a peace to the Boutaners, p. 468; and enters into a treaty of commerce with them, p. 469. Translation of the letter he received from the Tayshoo Lama, soliciting for peace, p. 489—492. Heat, a cause of the evaporation of water, p. 257. Heights of mines measured by the barometer, p. 401—449. The subterraneous geometer's method of finding these heights, p. 423, 424. Precepts and tables for calculating. calculating any accessible heights or depths from barometrical observations, p. 571—591. Easiest and best method of determining heights by the barometer, p. 683—686. 762, 763, n. Experiments and observations made in Britain, in order to obtain a rule for measuring heights with the barometer, p. 653. See Barometer. Heights determined by the barometer, p. 515—532. 539—546. 549, 550. 552—554. 592—597. Rule for measuring such heights, p. 686, 687. 734, 735. 757, 758. 762, 763, n. The rule which answers in middle latitudes will not in the frigid and torrid zones, p. 742—756. Remarks on the error of the rule in the tables of computation, and a method of bringing the theory of the barometer to greater perfection, p. 759—770. Computations of barometrical observations on various heights, p. 773—787. Hemming, Mr. Experiments with his electrical cylinder, some days after using it, on the balls of Canton's electrometer, p. 109—113. Henry, Mr. William, his experiments and observations in electricity, p. 85. See Electricity. His remarks on some experiments and observations on Mr. Volta's electrical machine, p. 117, 118. Hill, an account of a volcanic hill near Inverness, p. 385. See Volcanic Hill. Hills, mountains, and various other places, their heights taken by barometrical observations. See Heights. Honey-guide, or Cuculus Indicator, a curious species of cuckow in the interior parts of Africa, p. 43. See Cuckow. Honey-hunters, how conducted by the honey-guide to the wild bee-hives, p. 44. See Cuckow. Honig-wyzer, or honey-guide, p. 43. See Cuckow. Hovel, a description of one on The Mole, one of the Alps, p. 535. Huddart, Mr. Joseph, his account of some persons who could not distinguish colours, p. 260. See Colours. Hunter, Dr. and Mr. Henry Watson, their account of Dr. Maty's illness, and of the appearances in the dead body, p. 608—613. Husbands, a plurality of husbands allowed among the Thibetians, p. 477. Huffarzewski, a curious portrait of Copernicus in his possession, p. 33, &c. I. Jackson, Mr. his new method of soldering the piece of brass to the back of the little speculum of a telescope, p. 346. Jamaica, description of the Jesuits' bark-tree of that island, p. 504—506. Description and use of the cabbage-bark tree of Jamaica, p. 507—512. Jesuits' Bark Tree of Jamaica and the Caribbees, description of it, p. 504—506. Ignis satui explained, p. 142. Inquiries, philosophical; concerning them, p. 653, 654. Instruments, a number of curious ones in the Bramins' observatory at Benares, p. 599. In great-preservation, though erected two hundred years ago, ibid. Construction and situation of them, p. 599—601. Their description and use, p. 601—604—607. Invernetts, an account of a volcanic hill near there, p. 385. See Volcanic Hills. Journal, meteorological, for the year 1776, kept at the house of the Royal Society, p. 357—384. See Tables. Journey, an account of one into Africa from the Cape of Good Hope, and a description of a new species of Cuckow; p. 38. See African Cuckow. Jupiter's first satellites, eclipses thereof observed during the last ten years, concerning the difference of longitude at Paris and Greenwich, resulting therefrom; with a comparative table of the corresponding observations of the first satellite made in the principal observatories, p. 162—186. K. Kaunitzbl, in the Hartz, its depth determined by barometrical observations, p. 417—419, 436—440. L. Laabaffa, the capital of Thibet, some account of it, p. 481, 582. Its trade, p. 482—487. Lamp-black and tar, or lamp-black and oil, preserves the parts of masts of ships covered with it from injury by lightning, p. 85, 86. A curious instance of this kind, p. 86—89. Experiments in artificial electricity with lamp-black and oil, p. 89—91. Landmark, computations of barometrical observations made on heights near there, p. 775. Landen, Mr. John, his new theory of the rotatory motion of bodies affected by forces disturbing such motion, p. 266—295. Lava, an account of some discovered near Invernetts, p. 385—387. Lead-mines in the Ramelsberg near Goslar, method of working them, p. 414. Leather, its effect in experiments with the air-pump, p. 625, &c. Leek in Staffordshire, the remarkable case of a woman there, p. 458—464. Leiden bottle, Dr. Franklin's theory of it further illustrated, p. 100, &c. Lightning, parts of masts of ships preserved from its injury by being covered with lamp-black and tar, or lamp-black and oil, p. 85, 86. A curious instance of this kind, p. 86—89. Linboye, computations of barometrical observations made on heights near there, p. 779. Linseed-oil, the thick scum from its surface a very strong negative electric, p. 97, s. Lions, and other beasts of prey, frequently seen in Africa, p. 39, 40. Liverpool, observations on the annual evaporation there; and on evaporation considered as a test of the moisture or dryness of the atmosphere, p. 244. See Evaporation. A comparative view of the rain at Liverpool during the years 1772, 1773, 1774, and 1775, p. 247—250. A comparative view of the winds there during the same time, ibid. A comparative view of the temperature of the air there during the same time, ibid. London. The annual evaporation there, p. 252. Exceeds that at Liverpool, ibid. Meteorological journal for the year 1776, kept at London, p. 357—384. See Table. Computations of barometrical observations made on heights in and near London, p. 773. Longitude. Concerning the difference of longitude at Paris and Greenwich, resulting from the eclipses of Jupiter's first satellites, observed during the last ten years; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories, p. 162—186. Lyndon, in Rutland, extract of a register of the barometer, thermometer, and rain, kept there, for the year 1776, p. 350. State of the barometer for that year, ibid. Of the thermometer within and without, ibid. The quantity of rain which fell, ibid. A general account of the weather during that year, p. 351, 352. M. Machines. Of the degrees and quantities of winds requisite to move the heavier kinds of wind machines, p. 493—503. Experiments and observations on Mr. Volta's electrical machine, p. 116—118. Experiments on his machine for exhibiting perpetual electricity, p. 389—392. An experiment with a piece of dry and warm flannel tied round the globe of an electrical machine, p. 397, 398. Mackenzie, Dr. his account of a woman living without food or drink, p. 1. See Woman. MacLeod, Janet, the fasting woman in Ross-shire, her case, p. 1—11. Magnitudes. The general mathematical laws which regulate and extend proportion universally; or, a method of comparing magnitudes of any kind together, in all the possible degrees of increase and decrease, p. 450. The reasoning of geometers with respect to proportional magnitudes very confined, p. 450, 451. An investigation concerning it, p. 451—457. Male organs of generation, some resemblances of them in drones, p. 18. Manatee, one taken alive by the sea-side in Africa, p. 40. Manometer. Experiments on the expansion of air in the manometer, p. 689—696. Thermometrical spaces compared with those of the manometer, p. 697. Experiments for determining the actual expansion of common air in the manometer affected by the heat of 212°, p. 698—715. Maraldi, his notion concerning the propagation of bees, p. 17, 18. Drones as small as common bees discovered by him, p. 20, 21. Marsham, Mr. his account of the usefulness of washing and rubbing the stems of trees, to promote their annual increase, p. 12. See Trees. Maryport, in Cumberland, an account of a person there who could not distinguish colours, p. 260—265. Maseres, Francis, Esq; his method of finding the value of an infinite series of decreasing quantities of a certain form, when it converges too slowly to be summed in the common way by the mere computation and addition, or subtraction, of some of its initial terms, p. 187. See Quantities. Maskelyne, Rev. Dr. Nevil, an account of his new instrument for measuring small angles, called the prismatic micrometer, p. 799. See Micrometer. Masts of ships, those parts of them which were covered with lamp-black and tar, or lamp-black and oil, have escaped injury by lightning, p. 85, 86. A curious instance of this kind, p. 86—89. Mathematical articles, leading to a clear and satisfactory consideration of the motion of the earth's axis, p. 267—288. How the joint centrifugal force of a spheroid, or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. Mathematical laws, of those general ones which regulate and extend proportion universally; or a method of comparing magnitudes of any kind together in all the possible degrees of increase and decrease, p. 450—457. Mathematical problem, p. 283—288. See Problem. Mathematicians, almost all their geometrical reasoning is derived from Euclid, p. 450. Their reasonings with respect to proportional magnitudes very confined, p. 450, 451. An investigation concerning them, p. 451—457. May, Dr. a short account of his illness, and of the appearances in the dead body, p. 608—613. Megameter and micrometer, an account of a new one, p. 789—798. Metals... Directions for making the best composition for the metals of reflecting telescopes; together with a description of the process for grinding, polishing, and giving the great speculum the true parabolic curve, p. 296. See Telescopes. Meteorological Journal for the year 1776, kept at Bristol, 353. State of the barometer during that year, ibid. An abridged table of the winds for that year, p. 354. Quantity of rain which fell, ibid. Fair and frosty days, ibid. Monthly account of the weather, 354—356. Meteorological Journal for the year 1776 kept at the house of the Royal Society, p. 357—384. See Tables. Micrometer and megameter, an account of a new one, p. 789—798. An account of a new instrument for measuring small angles, called the prismatic micrometer, p. 799. Difficulties in the use of the object-glass micrometer, p. 799—801. Method of correcting recting its error, p. 801, 802. Description of an instrument for this purpose, p. 803—80. Remarks concerning its use, 809—812. Dr. Maskelyne the first inventor of it, p. 812—815. Mines. Barometrical observations on the depth of the mines in the Hartz, p. 401. See Barometrical observations. Concerning the air in mines, p. 412—416. Method of working the lead-mines in the Ramelsberg near Goslar, p. 417. The subterraneous geometer's method of finding the depths of these mines, p. 423, 424. Moisture or dryness of the atmosphere, evaporation considered as a test of it, p. 244. See Evaporation. The Mole, one of the Alps, an account of it, p. 533—539. Barometrical observations to ascertain its height, p. 539—546. 549, 550. Molyneux, Mr. Remarks on the defects in his method of polishing the speculum for reflecting telescopes, p. 318—320. A more perfect method of polishing and giving a correct parabolic figure to the metal at the same time, p. 327—335. Mont Saleve, one of the Alps, an account of it, p. 515, n. 527. Barometrical observations to ascertain its height, p. 515—532. 552—554. Concerning Mr. De Luc's observations thereon, 715, 716. 729, &c. Rule deduced from these observations, p. 655, 656. Expansion of quicksilver in the tubes of his barometers resulting from the observations, p. 656—658. Moon, its action upon the earth's axis considered, p. 267—288. Mortification. The treatment to stop a mortification, p. 460—461. Motion. A new theory of the rotatory motion of bodies affected by forces disturbing such motion, p. 266—295. Mountains, observations made in Savoy, in order to ascertain their heights by means of the barometer; being an examination of Mr. De Luc's rules, delivered in his Recherches sur les Modifications de l'Atmosphere, 513. Instruments used on this occasion, 515. First series of observations on Mont Saleve, ibid. Method of measuring it, p. 516, 517. Determination of the base, p. 518. Determination of the angles by the equatorial, p. 519, 520. Determination of the vertical angles, p. 521, 522. Determination of the sides, p. 523. Method of making the barometrical observations, p. 524—528. Comparison of the first series, p. 529. Comparison of the second series, p. 530. Comparison of the third series, p. 531. Barometrical rules a little defective as to the true ratio between the gravities of air and quicksilver, p. 532. Instruments used for making barometrical observations on the mole, p. 533, 534. Measurement of this mountain, p. 539, 540. Comparison of the first series of observation, p. 541. Comparison of the second series, p. 542. Comparison of the third series, p. 543. Comparison of the fourth series, p. 544. Comparison of the fifth series, p. 545. Comparison of the sixth series, p. 546. Barometrical rules defective by these experiments, p. 547. Remark thereon, p. 547, 548. Observations on the mole by M. de Saussure, making a defect of Mr. De Luc's rules, p. 549. p. 549, 550. Corresponding observation at Geneva, tending to prove the said defect, p. 551, 552. Other experiments on Mont Saleve, p. 552. Comparison of the first series, 553. Comparison of the second series, ibid. Comparison of the third series, p. 554. Comparison of the fourth series, ibid. All proving the existence of the defect in Mr. de Luc's rules, p. 554, 555. Quantity of the defect, from the result of all the barometrical experiments, p. 555, 556. An experiment to determine hydrostatically the specific gravities of air and quicksilver, with a given temperature and pressure, p. 557—561. Statical and barometrical experiments nearly agree, p. 561. A small difference in the equation for the expansion of air and quicksilver, by a change of temperature, from what Mr. De Luc's observations have given it, p. 562—569. Remarks on the foregoing inquiry, p. 569, 570. Precepts and tables for calculating any accessible heights or depths from barometrical observations, p. 571—597. Mountains of Thibet, musk-deer common there, p. 485, 486. Mudge, Mr. John, his directions for making the best composition for the metals of reflecting telescopes; together with a description of the process for grinding, polishing, and giving the great speculum the true parabolic curve, p. 296. See Telescopes. Musk-deer, common in the mountains of Thibet, p. 485, 486. Mutton, the Thibetians singular method of preparing it, p. 473. N. Nairne, Captain, his remarks on the parts of masts of ships covered with lamp-black and tar, or lamp-black and oil, escaping injury by lightning, p. 85, 86. Nairne, Mr. Edward, his account of some experiments made with an air-pump on Mr. Smeaton's principle; together with some experiments with a common air-pump p. 614. See Air-pump. Newton, Sir Isaac, the first proposer of polishing the metal for reflecting telescopes with pitch, p. 344. Pitch supposed to be the only substance in nature, that is perfectly calculated for that purpose, p. 345—347. North American Bison, the same as the great buffaloe in the wilds of Africa, p. 40. O. Object-glass micrometer, an error in its use, p. 799—801. Method of correcting the error, p. 801—812. Observatory. An account of the Bramins observatory at Benares, p. 598. See Bramins observatory. Oder Brucke, in the Hartz, its height above Clausthal determined by barometrical observations, p. 429. 444—449. Oil and lamp-black, or lamp-black and tar, preserve the parts of masts of ships covered, with it from injury by lightning, p. 85, 86. A curious instance of this kind, p. 86— p. 86—89. Experiments in artificial electricity with lamp-black and oil, p. 89—91. The thick scum from the surface of Linseed-oil, a very strong negative electric, p. 97. Oil-colours, electrical experiments on some, p. 394, 395. Oil-paint, over any substance, will defend it from a slight electrical shock, p. 394, 395. Olive-oil, melted with chocolate, will restore its electricity, p. 96. Paint. Oil-paint over any substance will defend it from a slight electrical shock: p. 394, 395. Painters. The old painters never gave that brightness to the eyes which the moderns do in their portraits, p. 35. The former came nearer to nature than the latter, ibid. Paper, painted with different oil-colours, electrical experiments on it, p. 394, 395. A coated phial may be charged with electrical sparks from a piece of paper, sufficiently to pierce a hole through a card with its discharge, p. 396. Paris and Greenwich, concerning their difference of longitudes, resulting from the eclipses of Jupiter's satellites, observed during the last ten years; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories; p. 162—186. Pear-gage, description of Mr. Smeaton's, p. 614—616. Quantity of permanent air remaining in the receiver of an air-pump when exhausted as much as possible, can be known only by this gage, p. 636, 637. The only means also of discovering what part of the receiver contains vapour, and what part permanent air, p. 637. Pendulum. Computation of the series which expresses the time of the descent of a pendulum through the arch of a circle, p. 215—230. A pendulum-rod of solid glass dilates much less than one of steel, p. 698, 699. Persons who could not distinguish colours; an account of three brothers, p. 260. See Colours. Peter's Rock, a volcanic hill near Inverness; an account of it, p. 385—387. Peru, no rain ever in that kingdom, p. 257. Its atmosphere during part of the year constantly obscured with vapours, and the whole country involved in thick fogs, p. 257, 258. Computations of Mr. Bouguer's barometrical observations in Peru, p. 787. Phial. A coated phial may be charged with electrical sparks sufficiently to pierce a hole through a card with its discharge, from a piece of new flannel, a hare's skin, or a piece of paper, p. 396. An electrical experiment on a phial, the inside coating of which was fluck with varnish, p. 398, 399. Philosophical inquiries; concerning them, p. 398, 399. Pine-apples. Extract of a letter from William Bastard, Esq; on the culture of pine-apples, p. 649. Method of raising pine-apples in water, p. 649—652. Pitch, Sir Isaac Newton the first proposer of polishing the metal for reflecting telescopes with it, p. 344. Supposed to be the only substance in nature that is perfectly calculated for that purpose, p. 345—347. Pliny, his opinion concerning the propagation of bees, p. 16. Pocket electrometer, description of one, p. 399, 400. Pole. The surface of the earth at the pole for ever covered with snow, p. 764. Pole-cat, (Viverra Putorius) a species of it found in Africa, p. 40. Politics and religion of the Thibetians, p. 473—479. Portrait of Copernicus, presented to the Royal Society by Dr. Wolf; an account of it, p. 33. See Copernicus. A portrait of him in the great church at Thorn, p. 34. Portraits. See Painters. Precepts and tables for calculating any accessible heights or depths from barometrical observations, p. 571—597. Prismatic micrometer; an account of a new instrument so called, for measuring small angles, p. 799. See Micrometer. Problem (mathematical). Suppose a given spheroid, whilst revolving uniformly about its proper axis, with a given angular velocity, to be suddenly urged by some percussive force to turn, with some given angular velocity, about a diameter of its equator; it is proposed to explain the rotatory motion of the spheroid consequent to the impulse so received, 283—288. Proportion. The general mathematical laws which regulate and extend proportion universally; or, a method of comparing magnitudes of any kind together in all the possible degrees of increase and decrease, p. 450—457. Pump. See Air-pump. Quantities (mathematical). A method of finding the value of an infinite series of decreasing quantities of a certain form, when it converges too slowly to be summed in the common way by the mere computation and addition, or subtraction of some of its initial terms, p. 187. Differential series, p. 187—190. Of the convergency of the foregoing differential series, p. 190—191. Of the investigation of the foregoing differential series, p. 191—194. Examples of the usefulness of the foregoing differential series in finding the values of infinite series whose terms decrease very slowly, p. 194. Computations of the lengths of circular arcs by means of infinite series derived from their tangents, p. 194—199. Computation of an arch of 30 degrees, p. 199—203. Computation of an arch of 45 degrees, p. 203—215. Computation of the series which expresses the time of the descent of a pendulum through the arch of a circle, p. 215—230. Queen-bees produced from the common eggs, p. 28—30. The working-bees have the power of making a queen of any worm in the hive, p. 30, 31. The received opinion that the queen-bees are produced from a particular kind of eggs, erroneous, p. 31. Quicksilver. An experiment to determine hydrostatically the specific gravities of air and quicksilver, with a given temperature and pressure, and remarks thereon, p. 557—570. Expansion of quicksilver in the tubes of Mr. De Luc's barometer, resulting from the Saleve observations, p. 656—658. Experiments on the expansion of quicksilver, p. 639—681. Rate of expansion of a column of quicksilver in the tube of a barometer, p. 682. Construction and application of a table of equation, for the expansion of quicksilver in the tubes of barometers, p. 683—686. The equation to be applied to the observed height of quicksilver in the barometer, from 15 to 31 inches; and for differences of temperature extending to 102° of Fahrenheit; whereby the column is reduced to the height it would have stood at in the temperature of 32 degrees, p. 687. The expansion of common air does not keep pace with the dilatations of quicksilver, p. 695. R. Rabbit's skin, a coated phial may be charged with electrical sparks from one, sufficiently to pierce a hole through a card with its discharge, p. 396. Smooth glass rubbed with a rabbit's skin acquires electricity, p. 397. Rain. Description of an electrometer for the rain, p. 51, 52. No rain ever in the kingdom of Peru, p. 257. The quantity of rain falling not so good a test of the state of the atmosphere as evaporation, p. 244, 245. A comparative view of the rain at Liverpool during the years 1772, 1773, 1774, and 1775, p. 247—250. Depth of the rain not a true index of the moisture or dryness of the atmosphere, p. 250—252. Why much rain gives no more moisture to the atmosphere than a little, p. 251. More rain falls than is raised in vapour, supposing the whole to be a surface of water, p. 254. Six times more descends in rain than what is exhaled from the earth, ibid. How the rain is collected and restored to the sources from whence it came, p. 254, 255. Annual fall of rain between Lancashire and Yorkshire, p. 255. Exceeds that of Liverpool, ibid. The quantity of rain which fell at Lyndon in Rutland during the year 1776, p. 350. What quantity fell in Bristol in the same year, p. 354. State of the rain for each month in London, throughout the same year, p. 358—381. Quantity which fell in each month, and in the whole year, p. 382. Rain-gage, wrong method of fixing it, p. 255. Ramelsberg near Goslar, in the Hartz, method of working the lead-mines there, p. 414. Depth of mines there determined by barometrical observations, p. 417—419, 436—440. Ramsden, Mr. description of his portable barometer, p. 658, 659. Reaumur, on the propagation of bees, p. 16, 18. He discovered drones as small as common bees, p. 21. Recherches sur les Modifications de l'Atmosphère, an examination of Mr. De Luc's rules delivered therein, by observations made in Savoy, in order to ascertain the height of mountains by means of the barometer, p. 513. See Mountains. Religion and politics of the Thibetians, p. 473—479. Report of the committee appointed by the Royal Society to consider of the best method of adjusting the fixed points of thermometers; and of the precautions necessary to be used in making experiments with those instruments, p. 816. See Thermometers. Republic of bees, the different sexes that constitute it, p. 19, 20. River, some account of the great river in the kingdom of Thibet, p. 481, 482. Rochon, Abbé; the first discoverer of a new micrometer and megameter, p. 789—792. See 812—815. Rogers, Rev. Mr. his certificate of the truth of the remarkable case of Ann Davenport, p. 464. Rome. Height of St. Peter's church at Rome determined by the barometer, p. 582. And of the Tarpeian rock there, p. 584. Ross-shire, an account of a woman there living without food or drink, p. 1. See Woman. Roy, Colonel William, his experiments and observations made in Britain, in order to obtain a rule for measuring heights with the barometer, p. 653. First part of the Rule, p. 686. Second part, p. 734, 735. Third part, 757, 758. See Barometer. Royal Observatories at Paris and Greenwich, concerning the difference of longitude at these places, resulting from the eclipses of Jupiter's first satellites, observed during the last ten years; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories, p. 162—186. Royal Society, a meteorological journal for the year 1776, kept at their house, p. 357—384. See Tables. The report of the committee appointed by the Royal Society to consider of the best method of adjusting the fixed points of thermometers; and of the precautions necessary to be used in making experiments with those instruments, p. 816. See Thermometers. Rubbing and washing the stems of trees increases their growth, p. 12—14. Rule for measuring heights with the barometer, 653. First part, 686. Second part, 734, 735. Third part, 757, 758. See Barometer. Roy. Saleve, Mont, an account of it, p. 515, n. 527. Barometrical observations to ascertain its height, p. 515—532, 552—554. Concerning Mr. De Luc's barometrical observations thereon, p. 715, 716, 729, &c. Rule deduced from the Saleve observations, p. 655, 656. Satellites. Eclipses of Jupiter's first satellites, observed during the last ten years, concerning the difference of longitude at Paris and Greenwich resulting therefrom; with a comparative table of the corresponding observations of the first satellite made in the principal observatories, p. 162—186. Savoy. Observations made in Savoy, in order to ascertain the height of mountains by means of the barometer, being an examination of Mr. De Luc's rules, delivered in his Recherches sur les Modifications de l'Atmosphere, p. 513. See Mountains. Scale of barometers, fixing them with cisterns recommended, p. 405, 406. The scale and glass tube of thermometers, their difference of expansion, p. 834. Shirach, his account of the sex of the working bees, p. 19, 21. Sea-anemonies, a third essay on them, p. 56. Observations on the generation of the fourth species of anemones, p. 57—78. A further observation on the first species p. 79—84. Sealing-wax, the best coating for glass-plates in electrical experiments, p. 389, n. Sex of bees, discoveries theron, explaining the manner in which their species is propagated, with an account of the utility that may be derived from those discoveries by the actual application of them to practice, p. 15. See Bees. The different sexes that constitute the republic of bees, p. 19, 20. Shafts, an account of the fine wool of which they are made, p. 485. Produced from the Thibetian sheep, ibid. Sheep. An account of the fine wool produced from the Thibetian sheep, p. 485. The shafts made of it, ibid. Ships. Parts of their masts which were covered with lamp black and tar, or lamp-black and oil, have escaped injury by lightning, p. 85, 86. A curious instance of this kind, p. 86—89. Short, Mr. his method of furnishing telescopes with Metals, p. 339, 340. Shuckburg, Sir George, his observations made in Savoy, in order to ascertain the height of mountains by means of the barometer, being an examination of Mr. De Luc's rules, delivered in his Recherches sur les Modifications de l'Atmosphere, p. 513. See Mountains. Smeaton, Mr. an account of some experiments made with an air-pump on his principle; together with some experiments with a common air-pump, p. 614. See Air-pump. Description of Mr. Smeaton's pear-gage, p. 614—616. Quantity of permanent air remaining in the receiver of an air-pump, when exhausted as much as possible, can be known only by his gage, p. 636, 637. It is also the only means of discovering what part of the receiver contains vapour, and what part permanent air, p. 637. Smith, Dr. defects in the compositions of metal recommended by him for the specula of reflecting telescopes, p. 297, 299. How this imperfection in the metal may be prevented, p. 300—303. Snow, the surface of the earth at the pole covered with it, p. 764, n. Sparrman, Dr. Andreas, his account of a journey into Africa from the Cape of Goodhope; with a description of a new species of cuckow, p. 38. See Africa Cuckow. Speculum. Speculum. Directions for making the best composition for the metals of reflecting telescopes; together with a description of the process for grinding, polishing, and giving the great speculum the true parabolic curve, p. 296. See Telescopes. Spheroid. How the joint centrifugal force of the particles of a spheroid or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. Spouts. Water-spouts occasioned by electricity, p. 141. St. Peter's church at Rome, its height determined by the barometer, p. 582. Stedman, Dr. John, on the degrees and quantities of wind requisite to move the heavier kinds of wind-machines, p. 493—503. Steel. A steel-pendulum-rod dilates much more than one of solid-glass, p. 698, 699. Stems of trees, the usefulness of washing and rubbing them, to promote their annual increase, p. 12. See Trees. Stewart, John, Esq. his account of the kingdom of Thibet, p. 465. See Thibet. Sting, none in drones, p. 25, 26. Strange, John, Esq. extract of his letters; with the Abbé Joseph Toaldo's letter to him, giving an account of the tides in the Adriatic, p. 144—161. Substance. An account of a hard substance extracted from a woman's groin, p. 461—463. Caused by a peg of wood which she had swallowed sixteen years before, p. 462, n. Sun, its action on the motion of the earth's axis considered in some mathematical articles, p. 267—288. How the joint centrifugal force of the particles of a spheroid or cylinder, having a rotatory motion about any momentary axis, is computed, p. 289—295. Swammerdam, on the propagation of bees, p. 16, 18. T. Tables. Observations on the electricity of the atmosphere, p. 50. Experiments with Mr. Hemming's electrical cylinder, for some days after using it, on the balls of Canton's electrometer, p. 109—113. Electricity of various substances discovered by a simple electrical apparatus, p. 122—126. Concerning the tides in the Adriatic, p. 151, 153. Æstus medius annorum, 1751—1755 et 1760—1769, p. 155. Æstus medius ratione situs Lunæ, p. 158. Tabula æstus maris, secundum xii. signa zodiaci, quatenus refertur ad Lunam, p. 160. Concerning the difference of longitude at Paris and Greenwich, resulting from the eclipses of Jupiter's first satellites, observed during the last ten years; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories, p. 163, 165, 167, 170—186. A comparative view of the evaporation, rain, winds, and temperature of the air, during the year 1772, at Liverpool, p. 247. TABLES. Comparative view of the same for the year 1773, p. 248. Comparative view of the same for the year 1774, p. 249. Comparative view of the same for the year 1775, p. 250. State of the barometer, thermometer, with what rain fell, at Lyndon in Rutland, during the year 1776, p. 350. State of the barometer at Bristol during the year 1776, p. 353. An abridged table of the winds, &c. for Bristol, for the year 1776, p. 354. Meteorological journal for the year 1776, kept at the house of the Royal Society, p. 357. State of the thermometer without and within, of the barometer, rain, winds, and weather, for January, p. 358, 359. For February, p. 360, 361. For March, p. 362, 363. For April, p. 364, 365. For May, p. 366, 367. For June, p. 368, 369. For July, p. 370, 371. For August, p. 372, 373. For September, p. 374, 375. For October, p. 376, 377. For November, p. 378, 379. For December, p. 380, 381. Greatest, least, and mean height of the thermometer without and within, and of the barometer, with the quantity of rain, in each month throughout the year, p. 382. Variation needle, p. 383. Dipping needles, p. 384. Barometrical observations determining depths and heights, p. 410—449. The proportion of winds of the second degree and upwards, to those of the first and below, for five years, p. 502. The proportion of fluids of the third degree and upwards, to those of the second and below, for five years, p. 503. Barometrical observations to ascertain the height of mountains, p. 518—531. 540—555. Observations on the expansion of air, p. 563. Precepts and tables for calculating any accessible heights or depths from barometrical observations, p. 571—597. Experiments with an air-pump, p. 628—635, 638, 641, 645, 646. Rate of Expansion of a column of quicksilver in the tube of a barometer, p. 682. The equation to be applied to the observed height of quicksilver in the barometer, from 15 to 31 inches; and for differences of temperature extending to 102° of Fahrenheit; whereby the column is reduced to the height it would have stood at in the temperature of 32°, p. 687. Thermometrical compared with manometrical spaces, p. 697. Results of experiments on the expansion of air, whose mean density was equal to two and a half atmospheres, p. 700. Results of experiments on the expansion of air of the density of five-sixths of the common atmosphere; and of others on air that was extremely rare, being only pressed with about one fifth of an atmosphere, p. 701. TABLES. Results of experiments on the expansion of air of the density of the common atmosphere, p. 703. Expansions for intermediate temperatures, p. 704. Results of experiments on the expansion of air, artificially moistened, by the admission of steam, and sometimes water, into the bulb of the manometer, p. 705. Heights determined geometrically, p. 717, 781. The equation depending on the temperature of the column of air, its elevation above the sea, as denoted by the mean height of mercury in the inferior and superior barometers, p. 771. Computations of barometrical observations made on heights in and near London, p. 773. Computations of barometrical observations made on heights near Taybridge, near Perthshire, and of those near Lanark, p. 775. Computations of barometrical observations made on heights near Edinburgh, p. 777. Computations of barometrical observations made on heights near Linhouse; and of those near Carnarvon in North Wales, p. 779. Computations of part of Mr. De Luc's barometrical observations, answering to the coldest and hottest temperatures of the air, p. 781—784. Computations of barometrical observations made on heights that have not been determined geometrically, p. 785. Computations of Mr. Bouguer's barometrical observations in Peru, p. 787. For adjusting the boiling point of thermometers, p. 854. For adjusting the freezing point of thermometers, p. 856. Tails. Remarkable cow-tails produced in the kingdom of Thibet, p. 484. To what use they are applied, p. 484, 485. The beast described, p. 484. Tar and lamp-black, or lamp-black and oil, have preserved the parts of masts of ships which were covered with it from injury by lightning, p. 85, 86. A curious instance of this kind, p. 86—89. Tarpeian Rock at Rome, its height determined by the barometer, p. 584. Tartars, heathen, who the great object of their adoration, p. 474—476. Taybridge, in Perthshire, computations of barometrical observations made on heights near there, p. 775. Tayboo Lama of the kingdom of Thibet, some account of him, p. 468, 475, 479—481. Translation of his letter to the governor of Bengal, soliciting a peace, p. 489—492. Telescopes. Directions for making the best composition for the metals of reflecting telescopes; with a description of the process for grinding, polishing, and giving the great speculum the true parabolic curve, p. 296. Enquiry concerning the composition for the specula of reflecting telescopes, p. 297—301. How to make the best metal for this purpose, p. 302, 303. Four tools only necessary for grinding and polishing it, p. 304. Of rough grinding the speculum, p. 304—306. The manner of forming the brass-grinding tool, p. 306, 307. How to form the bed of hones, or the third tool, p. 307, 308. The manner of forming the bruiser, p. 308, 309. How to procure washed emery for the working of these tools, p. 309. Of grinding the speculum, the brass tool, and the bruiser together, p. 309—311. The manner of figuring the metal upon the hones, p. 311—316. Remarks on Messrs. Hadley and Molyneux's method of polishing the speculum, p. 318—320. Experiments which led to a certain and easy method of giving an exquisite polish, and a correct parabolic figure to the metal at the same time, p. 321—327. How to polish the speculum, p. 327—333. How to give the parabolic figure to the metal, p. 333—335. To try the true figure of the metal, p. 338—341. Farther remarks on the process of polishing the speculum, p. 341—343. Test of a good telescope, p. 343, 344. Sir Isaac Newton first proposed the polishing with pitch, p. 344. Supposed to be the only substance in nature that is perfectly calculated for that purpose, p. 345, 347. Process for polishing the little speculum, ibid. A new method of soldering the piece of brass to the back of the little speculum, p. 346. Explanation of the figures on the plate, p. 348, 349. Theory. A new theory of the rotatory motion of bodies affected by forces disturbing such motion, p. 266. Thermometer, state of it at Lyndon in Rutland, during the year 1776, p. 350. State of it without and within in London, for each month throughout the same year, p. 358—381. Greatest, least, and mean height in each month, p. 382. The report of the committee appointed by the Royal Society to consider of the best method of adjusting the fixed points of thermometers; and of the precautions necessary to be used in making experiments with those instruments, p. 816. The quicksilver in the tube and in the ball should be of the same heat, and the ball not immersed deep in the water, p. 818, 835. Method of obtaining these requisites, p. 815. Experiments to determine the boiling point of thermometers, p. 818—833. Of the difference of expansion of the glass tube and the scale, p. 834. Concerning the correction necessary to be made when the quicksilver in the tube is of a different heat from that in the ball, p. 835—844. Rules to be observed in adjusting the boiling point, p. 845—855. On the freezing point, p. 856, 857. Precautions necessary to be observed in making observations with thermometers, p. 857. Tibet, or Boutan, an account of the kingdom of, p. 465. Hardly known to Europeans, ibid. Its situation, p. 466. The war which led to a farther discovery of this country, p. 467. The Europeans and Boutaners first meet at the attack of Cooch-Behar, ibid. Both greatly surprized at meeting with such a race of men, p. 467, 468. The Boutaners conquered by the Europeans, sue for peace, p. 468. The governor of Bengal grants a peace, and enters into a treaty of commerce with them, p. 468, 469. Description of the country, p. 469—471. Of the inhabitants, p. 470, 472. Their dress, p. 472. Food, p. 472, 473. Their religion and politics. ties; p. 473—479. Some account of their buildings, p. 479. Of its capital and trade, p. 481—487. Translation of a letter from the Tayshoo Lama to the governor of Bengal, soliciting a peace, p. 489—492. Thorn, a portrait of Copernicus in the great church there, p. 34. Tides. An account of the tides in the Adriatic, p. 145—161. Time, the Bramins method of reckoning it, p. 606. Toaldo, the Abbé Joseph, his account of the tides in the Adriatic, p. 145—161. Townley, Mr. his observations on the annual fall of rain between Lancashire and Yorkshire, p. 255. It exceeds that at Liverpool, ibid. An error in fixing his rainfall, ibid. Trees. On the usefulness of washing and rubbing the stems of trees, to promote their annual increase, p. 12. Tree cleared of moss and dirt with water and a brush, ibid. Washed with a coarse flannel, ibid. Washings frequent in dry times, ibid. Flourishing state of the washed tree compared with others of the same nature, p. 12—14. Description of the Jesuits' Bark-tree of Jamaica and the Caribbees, p. 504—506. Description and use of the Cabbage-bark tree of Jamaica, p. 507—512. V. Vapour, its effect in experiments with the air-pump, p. 625, &c. Its effect in the expansion of quicksilver, p. 670, &c. Vapours, the atmosphere of Peru constantly obscured with them during part of the year, and the whole country involved in thick fogs, p. 257, 258. Varnish. An electrical experiment on a phial, the inside coating of which was stuck with varnish, p. 398, 399. Viverra Putorious; a species of pole-cat, found in Africa, p. 40. Volcanic-hill; an account of one near Inverness, p. 385. Named Creek Faterick, or Peter's Rock, p. 386. Description of it, p. 386, 387. Evident marks of its having been a volcano, p. 386, and 387 n. No crater could be discovered, p. 386, 387. Another hill near Dingwal, in this country, supposed to be volcanic, p. 387. Volta's electrical-machine, experiments and observations on it, with remarks, p. 116—118. Experiments on his plates, commonly called a machine for exhibiting perpetual electricity, p. 389—392. W. Wargentin, Mr. Peter, his letter concerning the difference of longitude of Paris and Greenwich, resulting from the eclipses of Jupiter's first satellites, observed during the last ten years; with a comparative table of the corresponding observations of the first satellite, made in the principal observatories, p. 162—186. Washing and rubbing the stems of trees increases their growth, p. 12—14. Air an active solvent of water, in proportion to its dryness, p. 245—257. Heat, another cause of the evaporation of water, p. 257. Water may exist in air in three states, ibid. Remarks on these different states of water existing in air, p. 257—259. Water heavier than air, p. 560. On the exhalation of water in London, p. 252. And at Delft in Holland, ibid. Annual evaporation from water six times as much as it is from the earth, p. 253. The waters of the Ganges held in great veneration by the Tibetians, p. 478. Method of raising pine apples in water, p. 649—652. Water-colours, electrical experiments thereon, p. 392—394. Water-spouts occasioned by electricity, p. 141. Watson, Mr. Henry, and Dr. Hunter, their account of Dr. Maty's illness, and of the appearances in the dead body, p. 608—613. Wax, great quantities lost yearly for want of bees to collect it, p. 31, 32. Persons forming sticks of wax frequently discover electric attraction, p. 94, n. Sealing-wax the best coating for glass-plates in electrical experiments, p. 389, n. Weather, general state of it at Lyndon in Rutlandshire during the year 1776, p. 351, 352. Monthly account of it in Bristol for the same year, p. 354—356. State of the weather in London for each month throughout the same year, p. 358—381. Weft, Thomas, esq. his account of a volcanic-hill near Inverness, p. 385. See Volcanic-hill. Wild bee hives, how men are conducted to them by the honey-guide, a curious species of cuckow, p. 43—45. See Cuckow. Winds, a comparative view of them at Liverpool, during the years 1772, 1773, 1774, and 1775, p. 247—250. An abridged view of the winds at Bristol, for the year 1776, p. 354. State of the winds in London for each month throughout the same year, p. 358—381. Of the degrees and quantities of winds requisite to move the heavier kinds of wind-machines, p. 493. The proportion of winds of the second degree and upwards, to those of the first and below, for five years, p. 502. The proportion of winds of the third degree and upwards, to those of the second and below, for five years, p. 503. Effect of winds on the barometer, p. 751—753. Wind-machines. Of the degrees and quantities of winds requisite to move the heavier kinds of wind-machines, p. 493—503. Wolf, Dr. an account of the portrait of Copernicus, presented by him to the Royal Society, p. 33. See Copernicus. Woman. An account of one in the shire of Ross, living without food or drink, p. 1. The disorder brought on by epileptic fits, p. 2, 3. Her eye-lids lost their natural power, ibid. Menstrual discharges, and she monthly discharged blood from her mouth and nose, ibid. Took to her bed, and rejected food, p. 3. Totally refused food and drink, and her jaw became fast-locked, ibid. Lost her speech, p. 4, 5. Sensible of every thing that was said or done, p. 5. Swallowed nothing but two draughts of water. water for four years, ibid. No evacuation by stool, and scarcely any by urine, for three years, p. 5; 6. Her pulse distinct and regular, slow and small, p. 6. Countenance clear and pretty fresh, and her features neither disfigured nor sunk, ibid. Her body felt like that of a healthy young woman, ibid. Her knees bent, and hamstrings tight as a bow-string, ibid. She sleeps much and quietly, but keeps a constant whimpering when awake, p. 7. Her mouth soft and moist, ibid. State and condition of the patient five years after the above account was taken, p. 8. A few crumbs and a little moisture her only sustenance, ibid. Jaws still fast-locked, and she never attempts to speak, p. 9. Her hamstrings tight as before, and eyes shut, ibid. Her whole person rather emaciated, ibid. Still sensible and tractable in everything, ibid. Great improvement in her looks and health, p. 11. Takes more food, ibid. The account of this woman authenticated, p. 10, 11.—An account of a hard substance extracted from a woman's groin, p. 461—463. Caused by a peg of wood which she had swallowed fifteen years before, p. 462. Wood. An account of a hard substance extracted from a woman's groin, caused by a peg of wood which she had swallowed fifteen years before, p. 461—463. The effect of box-wood in experiments with the air-pump, p. 626, &c. Wool. An account of the fine wool from which the shauls are made, p. 485. Produced from a Thibet sheep, ibid. Worm-bark tree of Jamaica, its description and use, p. 507—512. Wright, Dr. William, his description of the Jesuits' Bark-tree of Jamaica and the Caribbees, p. 504—506. His description and use of the cabbage-bark tree of Jamaica, p. 507—512. The End of the SIXTY-SEVENTH VOLUME. The Number of Plates in this Volume is Twenty. The second, containing two different subjects, is marked Tab. II. at the Top, and Tab. III. below. The drawing of the eleventh Plate, having been sent in too late to be numbered in the regular series, is marked Tab. X. The letter-press tables should be bound in upon guards by the middle, to avoid any folding out; and in those which must be looked at side-ways, the page should lie towards the right-hand. ERRATA.