THE WAR WITH THE MICROBES. 1 



By E. A. de Schweinitz. 



From the moment that man made his appearance in the world there 

 has been perpetual warfare between himself and everything animate 

 and inanimate upon the earth. To a great extent this has been an 

 aggressive strife, man's every effort being exerted to compel nature to 

 contribute to his comfort, welfare, and advancement by the subjuga- 

 tion of her materials and forces. It was many centuries, however, 

 before he recognized that there were certain unknown insidious ene- 

 mies, which often rendered fruitless his simple household occupations, 

 defied his every effort at control, and sometimes menaced even his 

 well-being and life. Though in 1675 Leeuweahoeck discovered, with a 

 powerful magnifying glass, certain minute organisms in decomposing 

 animal matter, it was not until nearly two centuries later that their 

 true significance was recognized, and Davaine first demonstrated the 

 positive connection between these minute forms of life and disease. 

 When animal and vegetable life ceased, in accordance with the laws of 

 nature, they were supposed to be changed by purely chemical actions, 

 so that their elements were again returned to the earth and air to sup- 

 ply food for other plants and animals. This destruction was considered 

 to be wrought simply by the oxygen of the air, and the process of fer- 

 mentation was thought to be due to a similar cause. It had been 

 known for ages that the juice of the grape, if allowed to stand, under- 

 went changes by which its character was modified and wine was formed, 

 or this change might be allowed to progress further until the juice had 

 been converted into vinegar and finally carbon dioxid gas and water. 

 These alterations, those which take place in the digestive tract of ani- 

 mals and are involved in the conversion of dead animal and plant 

 matter into their simplest constituents, were classed under the general 

 head of fermentations. 



The fermentations, especially that of wine, an Italian chemist, Fa- 

 broni, in 1822, supposed to be induced by a substance of vegetable 

 origin, but closely allied to the white of egg. He considered this mate- 

 rial identical with the gluten of cereals and gave to it the name of 



1 Address of the president before the Chemical Society of Washington, March 9, 

 1897. Printed in Science, Vol. V, No. 119. pages 561-570. 



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