1889.] MrCROSCOPlCAL JOURNAL. 105 



Economic Yalue of Bacteriology.* 



By B. M. BOLTON, M. D. 



PROFESSOR OF PHYSIOLOGY, HYGIENE AND BACTBRIOLOGY IN THE UNIVERSITY OF SOUTH CAROLINA. 



In what way have the results of bacteriological investigations been 

 applied to matters of every-tlay life, and what can we expect from 

 them in the futui-e? Of course it is interesting, scientifically, to know 

 that infectious diseases, decomposition and fermentation are caused by 

 minute plants, and even if we could make no application of our knowl- 

 edge, the satisfaction of studying these facts amply rewards the student. 

 But aside from purely scientific interest, it is evidently of great use in 

 matters of common every-day life. In the first place, the benefit that 

 has been derived to the husbandman has been very great. After 

 Cagniard, Latour and Schwann established the fact that fermentation 

 is due to micro-organisms, Pasteur devoted himself to the study of 

 this phenomenon, and his results have saved the French people many 

 thousands of dollars. He found that the so-called diseases of wine are 

 due to bacteria. The souring of wine and the bitter taste which for- 

 merly caused great loss to the wine-growers of France are no longer 

 met with, for by heating the wine so as to kill the bacteria and then 

 sealing it up it does not sour or turn bitter. The silk industry of 

 France is equally indebted to Pasteur. He discovered the remedy for 

 an infectious disease which threatened to break up silk growing. 

 Pasteur also found that by the use of pure yeast the fermentation of beer, 

 the success of which was largely a matter of chance, renders it possible 

 for the brewers to rely upon their results. Although Pasteur's method 

 is a great improvement upon the old method of brewing, it has not 

 found as universal application as that introduced by Hansen. In Hol- 

 land and Germanv the brewers all use Hansen's yeast, which means 

 that they use pure cultures of veast fungus, which Hansen and others 

 found to make the best sort of beer. Instead of the uncertainty attend- 

 ing the manufacture of beer, which was formerly a source of great loss 

 to the brewers, they have no uneasiness upon this score at the present 

 day. Impure yeast causes beer to have a disagreeable taste. 



Bacteriological investigation has therefore been of advantage to the 

 wine, beer and silk industries, but the benefit in the prevention of in- 

 fectious diseases is still greater. It is not so much in the treatment of 

 each individual case, though even here much good has resulted, but in 

 the prevention of the spread of disease that the advantage is incalculable. 

 If an animal becomes sick, the bacteriologist can say, in many cases, 

 positively whether it is an infectious disease or not, and can isolate the 

 sick animal, so preventing the spread of the disease. It is of great im- 

 portance to diagnose the first case. Some of you. doubtless, remember 

 reading of several cases of cholera wliich occurred on board a vessel in 

 the port of New York about a year ago. A bacteriologist was im- 

 mediately sent for and declared the disease to be genuine Asiatic cholera, 

 and thus prevented the patients from being allowed to infect other per- 

 sons. The German government recognize the importance of diagnosing 

 the first case to such an extent that they required a number of marine 

 and army surgeons to go to Berlin and receive instruction from Koch 

 in his methods for studying the cholera bacterium. 



* From a report of the Department of Agriculture of South Carolina. 



