348 GERM-THEORY OP DISEASE. 



complexity of the fermentable bodies on the one hand, and the 

 complexity of the products of fermentation on the other. The 

 common ferment organism of putrefaction is the Bacterium termo, 

 with which others are unquestionably associated. 



As already indicated, many authorities regard the pathogenic 

 Schizophytes as constant species with constant physiological pecu- 

 liarities. Naegeli has most ably defended the opposite view, in. 

 accordance with which they are at most physiological varieties, and 

 points to the occurrence of new contagious diseases, and the sporadic 

 appearance of already known diseases, as confirmatory of his theory. 



Almost all the generic forms of Schizophytes have been recognized 

 in connection with one or other of the diseases of which they are now 

 generally believed to be the cause. Thus Micrococci have been 

 found in small-pox, diptheria, erysipelas, and some forms of blood- 

 poisoning ; Bacteria in septicaemia of the pigeon ; Bacilli in 

 anthrax, various forms of septicaemia, malaria, tuberculosis and 

 leprosy, and Spirochaete in relapsing fever. The list of diseases is 

 in fact being daily increased (especially by investigation into vai'ious 

 diseases of the domestic animals) with whieh specific pathogenic 

 Schizophytes (or Microbes, as the French investigators term them), 

 are found to be constantly associated. 



Since the establishment of the Germ-Theory of Disease on the 

 sound basis on which it now stands, increased interest has been 

 evinced in the microscopic examination of air and water, the chief 

 media from which the disease germs invade the body. With regard 

 to the latter microscopic examination cannot yet be regarded as 

 affording proof of the harmlessness or the reverse of water for 

 drinking purposes, although the examination of suspected water has 

 revealed in certain cases (Typhus-Brautlecht) micro-organisms to 

 which disease has been attributed. Chemical examination which 

 speedily reveals contamination by sewage, and therefore a possible 

 source of infection, is as yet to be more depended upon. No doubt 

 the researches on the Schizophytes which are now being carried on 

 may tend to render the microscopic analysis of water of greater 

 importance than it is at present. Michel and Hansen's observations 

 with regard to the occurrence of micro-organisms in the atmosphere 

 are of the highest interest. By far the greater number of the spores 

 found floating in the atmosphere belong to moulds, and are therefore 

 quite harmless to man. The same is probably true of the great 



