l64 PHILOSOPHICAL TRANSACTIONS. [aNNO 1771. 



phenomena : for as all smell, as much as we know at least till now, depends on 

 a saline matter, joined with a phlogiston, and the saline matter producing the 

 putrid stench, was not very likely an acid; I supposed it to be a volatile alkali, 

 which involved in phlogistic matter might fly off, before the alkali was developed. 

 I wanted to know, by experiment, if I was right; for this purpose I put, the 

 19th of June (the thermometer being 58 of Fahrenheit, and continuing between 

 58° and Ql^ all the time I observed), in a pretty large receiver, some beef cut in 

 very small pieces ; I covered the bottom with it thinly, and poured upon it 

 water, about 2 inches high. The 22d, the putrid smell was very sensible : but 

 I let it stand till the 24th, when I poured off the fluid,* adding again about the 

 same quantity of water to the flesh. I filtrated then the fluid through a piece of 

 fine linen, and mixed with some of it the syrup of violets, which it did not alter ; 

 neither did it effervesce with the spirit of vitriol, diluted to a sharpness near that 

 of the vegetable acid. I thought of keeping it in digestion for some days; but 

 for fear that some little solid particles might have passed through the linen, and 

 by that means, in growing putrid, might give some alkali, and render the trial 

 inaccurate, I distilled the fluid by a heat of about 1 6o°, after which I repeated 

 the trial with the syrup of violets and the spirit of vitriol ; but it produced no 

 change. I then put it, the 25 th, into a retort, fitted to it a receiver, applied 

 to the jointure a ring of paste made of flour and water, covered it with a piece 

 of wet bladder, and exposed it in a balneum arenas to a heat of 108" to ll6°, 

 till the 29th of June, when the whole fluid was distilled over. I perceived during 

 this operation, that the liquor, from being quite transparent, became turbid ; 

 the first distilled transparent fluid grew also turbid in the receiver, and at the 

 bottom of the retort there was a small settlement of a whitish earth. The liquor 

 had a particular smell, but quite different from a putrid one, inclining to the 

 volatile alkali ; and showed a slight but sensible degree of effervescence with the 

 spirit of vitriol ; and the syrup of violets was turned evidently green by it. 



In the mean time, the flesh with the water continued to emit a putrid stench ; 

 and the 28th of June I found the fluid colouring the syrup of violets greenish, 

 and showing a kind of effervescence with the acid. Both these qualities were 



autem ab eodem produci, quandoquidem superest eo sublato — \6. Videtur is odor a volatilibus ad- 

 modum particulis proficisci, sed quae ab alkali dissimiles sunt, plerumque citius gignantur, tardiusque 

 dissipentur — alcalescentia adesse potest modico foetori conjuncta — vicissim maximus foetor absque 

 alcali — Ex quibus differentia inter foetidas alcalinasque partes confirmari videtur. — P. S4', 17. Vide- 

 tur alcali non esse productum necessarium putrefactionis neque gradum alcalescentiae gradui putre- 

 factionis respondere. — Orig. 



• It requires some attention to find out the proper time when to pour off the liquor ; if it be done 

 too soon, it will give too little volatile alkali to be much sensible by experiments; for though 

 smells strongly, it is known how little matter is required to produce a strong smell. If it is delayed 

 too long, it shows already signs of an alkali. For that reason, 1 made many experiments in vain.— 

 Orig. 



