A Letter from George Lynn, Esq; To Ja. Jurin, M. D. F. R. S. Containing Some Remarks on the Weather, and Accompanying Three Synoptical Tables of Meteorological Observations for 14 Years, viz. from 1726 to 1739. Both Inclusive

Gulf of the Prostate. O. The Gulf of the Prostate. P.P.P. Sort of Elbows, or blind Cavities, found therein. Q. The Streights of the Entry into the Bladder. VI. A Letter from George Lynn, Esq; to Ja. Jurin, M.D. F.R.S. containing some Remarks on the Weather, and accompanying Three Synoptical Tables of Meteorological Observations for 14 Years, viz. from 1726 to 1739. both inclusive. SIR, Having, for these 14 Years last past, kept a constant Register or Diary of the Altitudes of the Barometer and Thermometer, the Quantity of Rain, Course of the Winds, &c. according to your Invitation (in the Philosophical Transactions;) the Five first Years of which have been by you communicated to the Royal Society, and taken notice of in the Transactions; I now, Sir, send you the remaining Nine Years at large, ending December 1739. in the same Method as formerly. But, believing it would be of good Use, both here and abroad, if the Mean Heights of the Barometer, Thermometer, and Quantity of Rain in every Month of the whole 14 Years, with the collateral Means, both of the Months and Years, were brought all into one View together, I have taken the Pains to range them accordingly in a Scheme, or Table, herewith sent, which does not take take up much above the Space of half a Sheet of Paper, and may be within Compass for inserting in the Transactions, either in a Plate, or otherways, as shall be thought proper. The Meaning of the several Columns in that Scheme is, in a great measure, explained by the Titles of them; and by the lowest Line you will find, that the Mean Height of the Inches. Barometer for the whole 14 Years is 29.58; the Mean Quantity of Rain annually, 23 Inches; and the Mean Altitude of the Thermometer \( \frac{56}{52} \) that is, at the coldest time of the Day 56, at the hottest 48, and their Mean 52. In the middle Column, viz. that of Rain, the Commas, Semicolons, and Colons, over the Figures, denote, by their manner of placing, from the Left to the Right, what Time in the Month the Rain fell, whether at the Beginning, Middle or latter End; the Comma [,] denotes a small Quantity, the Semicolon [;] a middling Quantity, and the Colon [:] a large Quantity; shewing the different Proportion that fell at those Parts of the Months. The Thermometer made use of all along, is that of Mr. Hawksby, and kept constantly in the same Place, as mentioned by Mr. Geo. Hadley in the Transactions, No 447. And the Altitudes of the Thermometer are taken but twice a Day, viz. at the coldest, which is at Sun-rise, or sometimes a little after; and at the hottest, viz. between Two and Four in the Afternoon: By which Method are gained the proportional Heats for every Month in the Year, and their Difference, as also between that of Day and Night, for 13 Years together; not reckoning in the Year 1726. which may be seen by the Scheme to be in another Method, and not filled up. Great Care has been taken, in casting up and dividing, to get the exact Mediums and Sums; and I was not a little surprised to find, in casting up the Column of the Mean Altitudes of the Thermometer collaterally, that as those for July, being the hottest Month, are $41^\circ$ so the Altitudes of June and August, on each Side of it, come out exactly equal to one another, and also those of May and September; these last only differing in their Morning and Evening Heats or Altitudes, which does not alter their Medium of $44^\circ$. Many other Observations may be made, both from the Scheme and Diaries at large, which, no doubt, will be taken notice of: But, having had ill Health of late, I am not able now to collect them, nor to form a Summary of the Winds, which I designed to have added some way or other in the same Scheme. As for any Judgment about the Weather, &c. it will be much better had from those who have the Perusal and Comparison of the many Meteorological Accounts sent to the Royal Society: I shall therefore only give a few cursory Notes of my own, as I find them, and so conclude this Letter. When there is an Haziness in the Air, so that the Sun's Light quails by Degrees, and his Limb is ill defined, it is a pretty certain Sign of Rain, especially if the Mercury falls. The like Haziness, at Night, is still more a Sign of it. It is observable, that though the Mercury, in the Summer Months, does not so much vary in its Altitude as at other times of the Year, yet in that Sea- son we have the most Rain: It should seem therefore, that the different Warmths (and consequently Rarefaction of Vapours) in the upper and lower Currents of the Air, and those Currents mixing, and sometimes wholly interchanging, are then the more immediate Causes of the Rains, if not also of Thunder and Lightning. Black fleecy Clouds, formed upon a sudden Flurry of the Wind, are generally succeeded by a Shower: And, The shifting of the Wind in a little time almost round the Compass, in hot Weather, is often succeeded by a Thunder-shower. Several times, when the Mercury has been a good while high, and so continues, there has fallen mistling Rain; especially about the New and Full Moon, with an Easterly Breeze, which the Borderers on the Coast of Lincolnshire and Norfolk call Tide-weather, and may be occasioned by the Vapours arising from the Tides, which then cover a vast Wash of Sands in their Neighbourhood. Those Vapours sometimes reach us here in Northamptonshire, but I believe seldom further West. The Nights are for the most part calmer than the Days; and the Winds seldom settled in their Quarter, or at their Strength, till some Hours after Sunrise, and generally die away again before Sun-set. I shall add no more, but that I am, Yours and the Society's most Obedient, Humble Servant. George Lynn. Southwick, April 21. 1740. N. Lat. 52°—31'. Synoptical Tables of the Meteorological Observations made by George Lynn, Esq; at Southwick, near Oundle in Northamptonshire, for the Years from 1726 to 1739. inclusively. The Barometer's Mean Altitude (above 29 Inches) in 100 Parts of an Inch, | In the Years | 1726 | 1727 | 1728 | 1729 | 1730 | 1731 | 1732 | |--------------|------|------|------|------|------|------|------| | January | .36 | .28 | .70 | .79 | .61 | .54 | | February | .51 | .86 | .66 | .39 | .57 | .65 | | March | .66 | .48 | .54 | .34 | .92 | .57 | | April | .75 | .72 | .48 | .60 | .66 | .51 | .52 | | May | .74 | .49 | .64 | .57 | .55 | .72 | .50 | | June | .63 | .58 | .68 | .69 | .60 | .66 | .71 | | July | .68 | .65 | .64 | .64 | .61 | .72 | .65 | | August | .45 | .77 | .64 | .72 | .70 | .65 | .70 | | September | .44 | .50 | .59 | .42 | .34 | .70 | .63 | | October | .77 | .44 | .38 | .52 | .49 | .67 | .68 | | Novemb. | .74 | .84 | .53 | .32 | .55 | .54 | .75 | | Decemb. | .50 | .33 | .51 | .52 | .83 | .61 | .47 | The Mean Altitudes in the several Years. The Barometer's Mean Altitude (above 29 Inches) in 100 Parts of an Inch, In the Years | | 1733 | 1734 | 1735 | 1736 | 1737 | 1738 | 1739 | |--------|------|------|------|------|------|------|------| | January| .68 | .80 | .47 | .26 | .86 | .70 | .45 | | February| .55 | .60 | .63 | .22 | .58 | .61 | .60 | | March | .43 | .52 | .36 | .44 | .45 | .46 | .48 | | April | .65 | .69 | .49 | .70 | .67 | .53 | .34 | | May | .70 | .54 | .60 | .58 | .70 | .52 | .60 | | June | .67 | .65 | .56 | .76 | .73 | .50 | .56 | | July | .67 | .63 | .50 | .67 | .59 | .72 | .67 | | August | .56 | .57 | .72 | .63 | .55 | .60 | .61 | | September| .62 | .56 | .69 | .71 | .46 | .65 | .49 | | October| .72 | .47 | .69 | .33 | .60 | .52 | .71 | | Novemb.| .75 | .74 | .45 | .64 | .68 | .67 | .32 | | Decemb.| .53 | .22 | .59 | .53 | .70 | .58 | .65 | The Mean Altitudes in the several Years. The Mean Altitudes collaterally. The Quantity of Rain in Inches and Decimals for every Month, In the Years | | 1726 | 1727 | 1728 | 1729 | 1730 | 1731 | 1732 | |--------|------|------|------|------|------|------|------| | January| 4.2 | 3.1 | 4.0 | 0.2 | 0.4 | 0.8 | 3.9 | | February| 1.0 | 2.6 | 0.9 | 0.5 | 1.5 | 1.0 | 1.2 | | March | 1.5 | 1.4 | 3.3 | 1.3 | 2.6 | 0.1 | 1.4 | | April | 1.0 | 1.2 | 2.0 | 1.1 | 0.8 | 2.1 | 1.2 | | May | 0.4 | 4.3 | 1.4 | 1.6 | 2.5 | 0.3 | 3.4 | | June | 4.0 | 3.2 | 2.8 | 0.8 | 3.4 | 3.4 | 0.6 | | July | 3.7 | 2.0 | 3.2 | 2.3 | 2.0 | 1.7 | 1.8 | | August | 0.3 | 0.3 | 1.0 | 2.4 | 0.8 | 1.6 | 1.7 | | September| 5.2 | 2.0 | 0.8 | 5.3 | 1.6 | 1.5 | 0.7 | | October| 1.5 | 1.5 | 2.8 | 2.2 | 3.0 | 1.4 | 3.7 | | Novemb.| 1.4 | 0.4 | 1.5 | 4.2 | 2.0 | 1.5 | 1.2 | | Decemb.| 2.5 | 2.8 | 2.4 | 1.7 | 0.8 | 2.3 | 2.6 | The Mean Quantity of Rain in the several Years: - 1726: 26.1 - 1727: 25. - 1728: 26. - 1729: 23 1/2 - 1730: 21. - 1731: 17 1/2 - 1732: 20.1 The Quantity of Rain in Inches and Decimals for every Month, In the Years | | 1733 | 1734 | 1735 | 1736 | 1737 | 1738 | 1739 | |--------|------|------|------|------|------|------|------| | January| 1.0 | 0.5 | 2.1 | 2.3 | 1.0 | 1.7 | 2.4 | | February| 1.4 | 2.6 | 0.7 | 2.9 | 2.2 | 0.8 | 3.1 | | March | 2.2 | 1.8 | 2.2 | 2.1 | 2.1 | 1.0 | 1.3 | | April | 1.0 | 0.6 | 1.7 | 0.6 | 0.4 | 1.3 | 2.2 | | May | 0.02 | 5.1 | 1.5 | 0.8 | 1.7 | 1.9 | 1.9 | | June | 2.0 | 1.3 | 2.4 | 1.4 | 1.8 | 3.4 | 1.5 | | July | 2.2 | 1.8 | 2.3 | 6.0 | 0.7 | 1.2 | 1.7 | | August | 3.6 | 4.0 | 3.2 | 1.7 | 5.7 | 1.6 | 2.5 | | September| 1.4 | 1.7 | 3.2 | 1.4 | 3.8 | 1.8 | 1.8 | | October| 0.6 | 2.8 | 1.7 | 2.6 | 1.8 | 1.8 | 0.8 | | Novemb.| 0.5 | 0.9 | 1.7 | 0.6 | 0.6 | 0.7 | 1.7 | | Decemb.| 1.7 | 4.4 | 2.1 | 2.0 | 2.3 | 1.2 | 1.9 | The Mean Quantity of the Rain in the several Years. \[ \frac{17\frac{1}{2}}{27\frac{1}{2}} = 25.\overline{2} \] \[ \frac{24.}{24.} = 18.\overline{2} \] \[ \frac{22\frac{1}{2}}{23}. \] The Thermometer's Mean Altitudes taken (from April 13th 1727.) at the coldest and hottest Time of the Day, and their Mean, In the Years | | 1726 | 1727 | 1728 | 1729 | 1730 | |--------|------|------|------|------|------| | January| | | | | | | | at 10 | at 3 | 65 | 68 | 66 1/2 | | February| | | | | | | | at 10 | at 3 | 59 | 57 | 68 | | March | | | | | | | | at 10 | at 3 | 62 | 58 | 64 1/2 | | April | | | | | | | | at 10 | at 3 | 40 | 23 | 52 | | May | | | | | | | | at 10 | at 3 | 25 | 20 | 42 | | June | | | | | | | | at 10 | at 3 | 36 | 31 | 37 | | July | | | | | | | | at 10 | at 3 | 37 | 31 | 36 | | August | | | | | | | | at 10 | at 3 | 40 | 31 | 35 1/2 | | September| | | | | | | | at 10 | at 3 | 43 | 43 1/2 | 48 | | October| | | | | | | | at 10 | at 3 | 52 | 51 | 54 | | Novemb.| | | | | | | | at 10 | at 3 | 62 | 63 | 64 | | December| | | | | | | | at 10 | at 3 | 70 | 69 1/2 | 71 | The Mean Altitudes of the Thermometer in the several Years. The The Thermometer's Mean Altitude taken at the coldest and hottest time of the Day only, and their Mean, In the Years | | 1731 | 1732 | 1733 | 1734 | 1735 | |--------|------|------|------|------|------| | January| 75169| 70165| 65158| 71165| 68142| | | 72 | 67 1/2| 61 1/2| 68 | 65 | | February| 70163| 61153| 64156| 61154| 66159| | | 66 1/2| 57 | 60 | 57 1/2| 62 1/2| | March | 63152| 64153| 64155| 59149| 64156| | | 57 1/2| 58 1/2| 59 1/2| 54 | 60 | | April | 62152| 56148| 57146| 56144| 55145| | | 57 | 52 | 51 1/2| 50 | 50 | | May | 50134| 53144| 54140| 53142| 53143| | | 42 | 48 1/2| 47 | 47 1/2| 48 | | June | 45131| 46134| 43139| 44134| 46137| | | 38 | 40 | 36 | 39 | 41 1/2| | July | 43129| 42131| 38127| 40131| 42135| | | 36 | 36 1/2| 32 1/2| 35 1/2| 37 1/2| | August | 42132| 47133| 45134| 42132| 43133| | | 37 | 40 | 39 1/2| 37 | 38 | | September| 49136| 49139| 52144| 51143| 46138| | | 42 | 44 | 48 | 47 | 42 | | October| 52146| 55147| 60152| 60153| 60152| | | 49 | 51 | 56 | 56 1/2| 56 | | Novemb.| 62157| 67162| 61155| 66162| 59154| | | 59 1/2| 64 1/2| 58 | 64 | 56 1/2| | December| 66161| 68164| 58153| 67163| 64160| | | 63 1/2| 66 | 55 1/2| 65 | 62 | The Mean Altitudes of the Thermometer in the Several Years. 56147 57148 55146 56148 56148 XXXII The Thermometer's Mean Altitude taken at the coldest and hottest time of the Day only, and their Mean, In the Years | | 1736 | 1737 | 1738 | 1739 | The Mean Altitudes collaterally | |--------|------|------|------|------|--------------------------------| | January| 64°50' | 63°59' | 63°57' | 63°58' | 67°62' | | | 62 | 61 | 60 | 60 1/2 | 64 1/2 | | February| 71°67' | 65°59' | 66°61' | 60°53' | 66°59' | | | 69 | 62 | 63 1/2 | 56 1/2 | 62 1/2 | | March | 63°54' | 65°58' | 62°54' | 65°57' | 63°55' | | | 58 1/2 | 61 | 58 | 61 | 59 | | April | 57°46' | 56°47' | 58°49' | 60°52' | 57°48' | | | 51 1/2 | 51 1/2 | 53 1/2 | 56 | 52 1/2 | | May | 54°44' | 49°35' | 46°36' | 49°37' | 50°39' | | | 49 | 42 | 42 | 43 | 44 1/2 | | June | 42°30' | 47°35' | 46°37' | 44°33' | 44°33' | | | 36 | 41 | 41 1/2 | 31 1/2 | 38 1/2 | | July | 41°31' | 41°29' | 42°30' | 41°32' | 41°30' | | | 36 | 35 | 36 | 37 | 35 1/2 | | August | 42°32' | 47°39' | 45°37' | 46°36' | 44°33' | | | 37 | 43 | 41 | 41 | 38 1/2 | | September| 49°38' | 47°40' | 51°43' | 48°41' | 49°40' | | | 43 1/2 | 43 1/2 | 47 | 44 1/2 | 44 1/2 | | October| 53°47' | 60°55' | 57°50' | 60°53' | 57°50' | | | 50 | 57 1/2 | 53 1/2 | 56 1/2 | 53 1/2 | | Novemb.| 62°57' | 62°56' | 63°57' | 68°63' | 63°58' | | | 59 1/2 | 59 | 60 | 65 1/2 | 60 1/2 | | December| 63°60' | 67°65' | 65°62' | 70°66' | 66°63' | | | 61 1/2 | 66 | 63 1/2 | 68 | 64 1/2 | The Mean Altitudes of the Thermometer in the several Years | | 55°47' | 56°48' | 55°48' | 56°48' | 56°48' | |--------|--------|--------|--------|--------|--------| | | 51 | 52 | 51 1/2 | 52 | 52 |