110 Mayow 



mixed with the too highly exalted saline-sulphureous 

 particles of purulent matter, excite a very intense 

 eifervescence and febrile heat. 



When saline-sulphureous and nitro-aerial particles 

 effervesce so much in long-continued fevers, it comes 

 about that the volatile salts of the blood are so worn 

 that they change at last, in the manner already 

 described, into acid salts. And hence it is that the 

 blood acquires an acid nature after long-continued 

 fevers ; indeed the case is not very different from 

 that of strong ale, which after long fermentation is 

 converted into vinegar. Nay, even when the fer- 

 mentation of the blood goes on aright, its saline 

 particles are in course of time sharpened and liquefied 

 by the action of the i nitro-aerial spirit, and in 

 combination with other (volatile) salts constitute a 

 certain acido-saline salt not very unlike Sal-Armoniac. 

 And thus it is that urine is impregnated with a certain 

 Sal-Armoniac, and the proof of this is that copper 

 is corroded by urine in the same way as by Sal- 

 Armoniac. Further, a solution of sulphur made in 

 lye is precipitated by urine poured on it just as by 

 any acid liquid. Hence if ashes have urine or even 

 blood mixed with them, volatile salt will in distillation 

 be abundantly derived from them, inasmuch as the 

 fixed salt of the ashes absorbs whatever of acid there 

 is in the urine, so that its volatile salt, freed from the 

 acid salt, readily ascends, precisely as happens in dis- 

 tilling Sal-Armoniac mixed with fixed salt. 



Besides the uses thus far assigned to nitro-aerial 

 spirit, a very great many other offices are served by it. 

 For when nitro-aerial particles effervesce with the 

 mass of the blood in the manner aforesaid, its saline- 

 sulphureous particles are brought to due volatility, 

 just as the sulphureous particles from terrestrial matter 



