210 PROCEEDINGS OF SOCIETIES. 



diseases, such as " the blood " in sheep, small-pox, vaccine-pox, 

 puerperal fever, silkworm diseases, &c., do not belong to the moving 

 cylindrical bacteria of putrefaction, but to the motionless, often 

 beaded spherical bacteria. With respect to the propagation of 

 contagion Cohn points out the great importance of drinking water, 

 and has detected in waters which have been suspected to convey 

 disease, a high degree of putrescibility, or even already existing 

 putrescence, which is also shown by the large amount of albumi- 

 nous or even ammoniacal compounds. 



