VOL. XLVI.] PHILOSOPHICAL TRANSACTIONS. 87 



thin and resolve it, but are not therefore septics. For so little do these salts 

 putrefy, or even resolve the fibres, when applied dry, that he had kept, since 

 the beginning of June last, notwithstanding the excessive heats, a small piece of 

 flesh in a phial, preserved only with salt of hartshorn, at present perfectly sound, 

 and firmer than when first salted. 



7. From the specimens he had of the antiscorbutic plants, it is likewise probable 

 that none of that tribe will prove septic. Horse-raddish, one of the most acrid, 

 is a very powerful antiseptic. And though carrots, turnips, garlick, onions, 

 celery, cabbage, and colewort, were tried, as alcalescents, they did not hasten, 

 but somewhat retarded the putrefaction. 



8. The case was different with such farinaceous vegetables as were examined, 

 viz. white bread in infusion, decoctions of flour, barley, and oatmeal; for these 

 did not at all retard putrefaction: but, after it was somewhat advanced, they 

 checked it by turning sour. By a long digestion the acidity became considerable ; 

 which, by conquering the putrescency of the flesh, and generating much air, 

 did not ill represent the state of weak bowels, which convert bread, and the 

 mildest grains, to such an acid, as prevents a due resolution and digestion of 

 animal food.* 



g. He examined cantharides, dried vipers, and Russian castor, all animal sub- 

 stances, and therefore most likely to prove septic. The flies were tried both with 

 fresh beef, and with the serum of human blood: the vipers only with the former: 

 but neither of them hastened putrefaction. And as for the castor, so far from 

 promoting this process, that an infusion of 12 grs. opposed it more than the 

 standard salt. 



10. After finding no septics where they were most expected, he discovered 

 some which seemed the least likely; viz. chalk, the testacea, and common salt. 

 20 grs. of crabs'-eyes prepared, were mixed with 6 drs. of ox's gall, and as much 

 water, into another phial was put nothing but gall and water, in the same quan- 

 tity with the former; and both being placed in the furnace, the putrefaction 

 began much sooner where the powder was than in the other phial. He infused 

 afterwards in the lamp furnace 30 grs. of prepared chalk, with the usual quantity 

 of flesh and water; and observed, that the corruption not only began sooner, . 

 but went higher by this mixture; nay, what had never happened before, that in 

 a few days the flesh resolved into a perfect mucus. The experiment was repeated 

 with the same effect ; which being so extraordinary, he suspected some corrosive 

 substance had been mixed with the powder; but, for a trial, a lump of chalk 



* It is to be remarked that, in making this experiment. Dr. P. did not then attend to a fermenta- 

 tion that ensued, and which was the cause of the acidity. This kind of fermentation between 

 ammal and vegetable substances, being hitherto overlooked, is set forth in the next paper. — Orig. . 



