THE MICROSCOPE. 31 



have been compelled to fall back on old principles and old remedies. 

 Curing a cancer, where it had nearly destroyed a uterus, with chian 

 turpentine; or phthisis with hypophosphites, where extensive tuber- 

 culosis existed, is something more gross and tangible; and are things 

 in which we are not so liable to be mistaken as in minute microscrop- 

 ical examinations, where the rays of light that reach the eye are 

 necessarily few. 



The great discovery of Koch, of the "'bacillus tuberculosis," ap- 

 peared to show progress; but Dr. Schmidt, of New Orleans, would 

 set us back where we stood years ago, and tell us what Koch dis- 

 covered were no bacilli at all, but only fat-crystals. And there are 

 other reasons, apart from Dr. Schmidt's experiments, to show that 

 this is true. 



According to Koch, it is in the earlier stages of tuberculosis 

 that these "bacilli " appear most numerous ; the very time at which 

 the tissues are best supplied with fat. But when the disease has 

 progressed, and the system almost succumbed to the influence of 

 these organisms, they are frequently not found at all. They are 

 absent when we would expect them in their greatest profusion. If 

 consumption be caused by them, tubercle is their natural soil, and 

 in its softened state, they would grow in their greatest luxuriance. 

 If those objects be fat crystals, we would expect their disappear- 

 ance as the disease progresses ; if bacilli, we would expect their 

 increase. 



It is a settled point that many persons seeing, or thinking they 

 saw, the same object, is not positive evidence of its existence. We 

 were first told that those " bacilli" could only be seen after staining 

 in a peculiar manner discovered by Koch. We are now told of 

 various other modes of preparation ; and that (although they were 

 patiently searched after for years without being found) they may 

 be seen without any particular preparation at all. 



Baumgarten wishes to lay claim to this discovery, and proceeds 

 to prepare the specimen in accordance with the supposed fact that 

 the tubercle bacilli will remain absolutely colorless under a staining 

 process, while the accompanying matter will take the coloring. 

 Ehrlich takes the opposite position, and holds that the "bacilli" 

 are not only readily stained, but that they hold it with such pertinac- 



4 



ity, that they will not part with it in diluted nitric acid, while the 

 other portions of the specimen will be bleached. Koch also claims 



