370 
ALFKKI) L. LOOMIS. 
whether the bacilli found in sputum, for example, are from 
tubercle or are the bacteria of decomposition. 
From what I have said of the tubercle bacillus it would seem 
as thoroughly demonstrated that it was the cause of tubercle in 
these animals. But we must'walk cautiously here. These are 
not human beings; who knows that like results would follow 
their inoculation ? The animals used by Koch are animals very 
subject to tubercle. 
We must, from the very nature of our environment, be con. 
stantly inhaling these germs as we pass through the wards of our 
hospitals—yes, they are floating in the air of our streets and 
dwellings. It becomes necessary for us to inquire, If bacteria 
cause disease, in what manner do they produce it ? Ziegler 
says: “The healthy organism is always beset with a multitude of 
non-pathogenous bacteria. They occupy the natural cavities, 
especially the alimentary canal. They feed on the substances 
lying in their neighborhood, whether brought into the body, or 
secreted by the tissues. In so doing they set up chemical 
changes in these substances. While the organs are acting nor¬ 
mally these fungi work no mischief. The products of decompo¬ 
sition thus set up are harmless, or are conveyed out of the body 
before they begin to be active.” If bacteria develop to an inordi¬ 
nate extent, if the contents of organs are not frequently discharged, 
fermentation processes may be set up, which result in disease. 
Bacteria must alway multiply and exist at the expense of the body 
which they infest, and the more weakened the vital forces become 
the more favorable is the soil for their development. 
Septicaemia is caused by the absorption of the products of 
putrefaction induced by bacteria. Before bacteria can multiply 
inside or outside the body they must And a congenial soil. The 
so-called cholera bacillus must gain access to the intestinal tract 
before it finds conditions suitable to colonization. They do not 
seem to multiply in the stomach or in the blood, but once injected 
into the duodenum they develop with astonishing rapidity. The 
delicate epithelial cells of the villi become swollen, soften, and 
break down, exposing the mucosa 
But it becomes us to proceed in this matter with great cau- 
