VOL. XLVI.] PHILOSOPHICAL TRANSACTIONS. SQ 



appeared on shaking the glasses. On the whole, though there were some marks 

 of a latent alkali in the putrid serum, they were so very faint, that one drop of 

 spirit of hartshorn in a quantity of water equal to that of the putrid liquors, 

 showed more of an alkali than 20 drops of any of the other. 



2. It has been a maxim, that all animal substances, after putrefaction, being 

 distilled, send forth a great quantity of volatile salt in the first water ; but Mr. 

 Boyle (Nat. Hist, of Human Blood, vol. iv. p. 178, fol. ed.) found that this held 

 good only in urine ; and that in the distillation of the serum of human blood 

 putrefied, the liquor which first came over had little strength, either as to its 

 smell or taste, and did not at first effervesce with an acid. And here it may be 

 observed, that the chemists have generally applied those properties they discover 

 in urine, to all the humours indifferently; whereas in fact there is a great diver- 

 sity. For some animal substances, such as urine and bile, soon putrefy ; the 

 saliva and the white of an egg slowly. Yet those that soonest corrupt do not always 

 arrive at the highest degree of putrefaction. Thus the bile is soon corruptible, 

 but the rankness of it is not to be compared to that of flesh; and the white of an 

 egg is not only much less disposed to putrefy than the yolk, but, when corrupted, 

 yields a different and less offensive smell. And it seems particular to stale urine 

 to contain an alkaline salt, which, without distillation, makes a strong effer- 

 vescence with acids : whereas most other animal humours putrefied, though of a 

 more intolerable fetor, yet contain less volatile salt, less extricable, and not effer- 

 vescing with acids. But what makes the difference between stale urine and other 

 putrid substances still more specific, is its inoffensiveness with regard to health ; 

 while the steams of most other corrupted bodies are often the cause of putrid and 

 malignant diseases. 



Now, on finding in urine a much greater quantity of volatile salt, and that 

 more easily separable than in any other humour, and that stale urine is the least 

 noxious of putrid animal substances, so far then from dreading the volatile al- 

 kali as the deleterious part of corrupted bodies, from this instance we may rather 

 infer it to be a sort of corrector of putrefaction. 



3. Daily experience shows how harmless the volatiles are, both when smelled 

 to, or taken in substance ; but still there remains a prejudice, as if these salts, 

 being the produce of corruption, should therefore hasten putrefaction ; not only 

 in distempers where these salts are unwarily taken, but also in experiments out 

 of the body. 



Now, as to the effects arising from the internal use of them, little can be said, 

 unless the kind of disease was precisely stated. For supposing they were by 

 their nature disposed to promote putrefaction ; yet if that is already begun, from 

 a languor of circulation, and obstruction, then may the volatiles, by their stimu- 

 lating and aperient quality, be the means of stopping its progress: and on the 



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