Proceedings of the Polytechnic Association. 1067 



in the former case, and veo'etable in the second. Here tlie carbolic 

 acid eoagulatinw the albumen on the surface of the corpuscle, forms 

 an insoluble envelop impenetrable to air, and to further quantities 

 of earl)olic acid, which in this manner forms an obstacle to the entrance 

 of itself into the interior of the body. This retains in its center a 

 minute portion nnchanged, full of life, capable of increase under 

 favorable circumstances, and protected from external influences by its 

 coating of coagulated albumen. Such a corpuscle acted on by carbolic 

 acid, may be represented by an egg exposed to boiling water for a few 

 seconds. The coagulating influence of heat aftects the superficial 

 layer of albumen, which still incloses the rest of the egg in its raw 

 state All substances or processes producing the same coagulating 

 effect upon albumen do in reality exert the same destructive influence 

 upon contagion and miasma, but do not possess those necessary 

 properties which qualifies them for this purpose as well as carbolic 

 acid. Heat, which coagulates albumen, has been used successfully 

 in the disinfection of clothing and places infested with the poison of 

 cholera, yellow fever, &c.; but while we can turn high pressure or 

 even superheated steam into a room, a ship, &c., we cannot subject a 

 cholera patient, or an animal infected with the cattle plague, to so 

 high a temperature as to destroy the poison lurking within them ; 

 and if in diluted carbolic acid we have a remedy which, with such 

 coagulation, will destroy the activity of the contagion without inter- 

 fering with the process of life in the patient, we have found a 

 desideratum which is at once a boon to mankind and a victory of 

 science important beyond comparison. The use of other chemicals 

 as the mineral acids, and their salts, which coagulate albumen, is 

 precluded in contagious diseases, under the same circumstances, and 

 for similar reasons, under which superheated steam is unavailable. 

 On the other hand, carbonic acid greatly diluted exerts a barely per- 

 ceptible influence upon the vital processes of the largest animals, 

 while its powers of destroying sporules is almost equal to that of the 

 concentrated acid. This apparent anomaly is easily explained on 

 comparing its action to the parallel coagulation of a highly diluted 

 solution of albumen by one similarly diluted of the acid. The diluted, 

 solution is as completely coagulated as a dense one ; but the dilution 

 of the liquid places the particles of albumen at such great distances 

 from each other that they can no longer form a coherent mass after 

 coagulation, but remain separately suspended in the liquid, rendering 

 it opaque and milky in appearance. This liquid, although charged 



