Praeparatio Caerulei Prussiaci Ex Germania Missa ad Johannem Woodward, M. D. Prof. Med. Gresh. R. S. S.

but a number of little Globules, cluster'd together, that differ'd in their Roundness, Form, Colour, and Consistence, proceeding from little seminary Vesicles in a Cluster. Some had Water extremely clear and liquid, others a yellowish Serum thin, others a glutinous Matter; some were as big as Pullets Eggs, others bigger than one's Fist. Let these few, out of the many Instances which I could produce from Authors of undoubted Reputation, suffice to prove, that the Ovaria, as well as the Tubæ Falloppianæ, Ligaments, and Uterus itself, are not free from Dropsies, &c. and that they proceed from Obstructions, often occasioned by rude and violent dealing with Women in difficult Labours, which generally bring on a train of dismal Symptoms, that sooner or later, according to the Strength of the Sufferer, after a miserable, painful, languishing Life, end in Death. The manifest Success in this uncommon Case may be of use, and may shew, that we ought not to despair too soon, in Distempers that are seemingly most dangerous. IV. Præparatio Cærulei Prussiaci ex Germaniâ missa ad Johannem Woodward, M.D. Prof. Med. Gresh. R. S. S. Tartari crudi & Nitri crudi Siccati ad 3iivi. Pulverifentur minutissime, & commisceantur, deinde admoto igneo carbone detonentur, & habebis Salis Tartari extemporanei 3iivi. Dum adhuc calidum est hoc Sal, pulverifetur subtilissime, & addantur sanguinis Bovini probe exsiccati & subtiliss. pulv. 3iivi. Hæc bene bene mixta, indantur crucibulo, ut tertia pars vacua sit; imposito dein operculo igni committatur, & circumdetur crucibulum carbonibus, ut sensim ardecat, & materia sine praepropera accensione flammane concipiat & ignescat. In hoc ignis gradu teneatur materia, donec flamma & accensio remittat; augeatur demum ignis, ut valde candeat materia, & parum flammæ e crucibulo amplius emineat. Remove demum ab igne crucibulum, & materiam mortario ingestam leviter contere, & ad manus habeto aquae ferventissimæ pluvialis libras 4 ponderis civilis, cui materiam, adhuc ferventem, immittas, & per semihoræ spatium coque; decoctum per linteum coletur, & materia remanens nigra, aquæ portioni denuo affusa, igni iterum apponatur, coquatur, & percoletur; id quod eousque continuandum; donec falsedo & acrimonia omnis e materia sit elixiviata, & aqua redeat insipida. Humores omnes in linteo & materia residuos, fortiter exprime, & ubi singula in unum colligeris, igni iterum committe, & ad remanentiam 4 librarum evapora, & ulteriori usui serva, sub. No. 1. R. Porro Vitrioli Anglici ad albedinem leviter calcinati 3i. solvatur in Aquæ pluvial: 3vi. filtretur per chartam & signetur: No. 2. R. Denique Aluminis crudi 3viii. Solvatur in libris 4. aquæ ferventissimæ ad omnimodam Aluminis consumptionem, hoc rite peracto, adjunge solutionem Vitrioli sub No. 2. asservatam, quæ ex igne fervens ingeratur ollæ satis magnæ & amplæ, & cum lixivio No. 1. seorsim bene fervefacto, combinetur. Fiet ex continenti magna ebullitio, & apparebit color viridis montani seu chrysocolla; effundatur alternis vicibus, durante ebullitione, ex uno vase in aliud, qua cessante, quieti committe. Tum linteo insinuetur, ut aquositas transeat, color vero in linteo remaneat; si igitur nihil humiditatis amplius distillet, cum spathula lignea e linteo é linteo in ollam novam minorem remove; superfunde postea spiritus salis comm. 3ii. vel 3iii. & statim apparebit color cæruleus pulcherrimus: quae probe mixta per noctem quiescant, quo facto aquæ pluvialis magna quantitas addatur, in gyrum moveatur spatula, & posteaquam rededit materia, aqua decantetur, & recens aqua superfundatur, & eoque labor reiteretur, donec omnis acrimonia sit defumpta, & aqua insipida defluat; hoc pacto præcipitatum tuum summè cæruleum linteo expanso ingere, ut aqua distillet, sensimq; color calore leni exsiccetur usui. N. B. Calcinationis magni momenti est in hoc opere, nam color cyaneus & cæruleus obscurus ortum suum trahit a calcinatione levi, mediocri, & fortissimi sanguinis artefacti cum salé Tartari, & inde diversitas coloris. Lixivia ferventissima uno eodemque festinatissimo actu sunt confundenda. V. Observations and Experiments upon the foregoing Preparation. By Mr. John Brown, Chymist, F. R. S. Dr. Woodward having lately communicated a Paper (which he receiv’d from another hand) to this Society, containing a Process for making the Prussian Blue. I was willing to go thro’ it exactly, according to the Proportions there prescrib’d; and observ’d that by a Calcination of 3 4 of Blood dry’d, with 3 4 of Sal Tartari, in two Hours time that Part of the Operation was over, and a black spongy Substance remain’d in the Crucible weighing 3 4. a Dissolution of which being made in boiling Water and afterwards filtr’d, the Remainder, when dried, weigh’d Vol. XXXIII. D 9 Drachms,