FERMENTATION AND DISEASE. 153 



these changes, traced them to their living causes, and showed that the 

 permanent health of the vinegar was insured by the destruction of 

 this life. He passed from the diseases of vinegar to the study of a 

 malady which a dozen years ago had all but ruined the silk-husbandry 

 of France. This malady, which received the name of pebrine, was the 

 product of a parasite which first took possession of the intestinal canal 

 of the silkworm, spread throughout its body, and filled the sack which 

 ought to contain the viscid matter of the silk. Thus smitten, the 

 worm would go automatically through the process of spinning when 

 it had nothing to spin. Pasteur followed this parasitic destroyer from 

 year to year, and, led by his singular power of combining facts with 

 the logic of facts, discovered eventually the precise phase in the de- 

 velopment of the insect when the disease which assailed it conld with 

 certainty be stamped out. Pasteur's devotion to this inquiry cost him 

 dear. He restored to France her silk-husbandry, rescued thousands 

 of her population from ruin, set the looms of Italy also to work, but 

 emerged from his labors with one of his sides permanently paralyzed. 

 His last investigation is embodied in a work entitled " Studies on 

 Beer," in which he describes a method of rendering beer permanently 

 unchangeable. That method is not so simple as those found effectual 

 with wine and vinegar, but the principles which it involves are sure 

 to receive extensive application at some future day. Taking into 

 account all these labors of Pasteur, it is no exaggeration to state that 

 the money value of his work would go far to cover the indemnity 

 which France had to pay to Germany. 



There are other reflections connected with this subject which, even 

 were I to pass them over without remark, would sooner or later occur 

 to every thoughtful mind in this assembly. I have spoken of the float- 

 ing dust of the air, of the means of rendering it visible, and of the 

 perfect immunity from putrefaction which accompanies the contact 

 of moteless air. Consider the woes which this wafted matter, during 

 historic and prehistoric ages, has inflicted on mankind ; consider the 

 loss of life in hospitals from putrefying wounds ; consider the loss in 

 places where there are plenty of wounds but no hospitals, and in the 

 ages before hospitals were anywhere founded; consider the slaughter 

 which has hitherto followed that of the battle-field, when those bacte- 

 rial destroyers are let loose, often producing a mortality far greater 

 than that of the battle itself; add to this the other conception- that 

 in times of epidemic disease the self-same floating matter has fre- 

 quently, if not always, mingled with it the special germs which pro- 

 duce the epidemic, being thus enabled to sow pestilence and death over 

 nations and continents consider all this, and you will come with me 

 to the conclusion that all the havoc of war, ten times multiplied, would 

 be evanescent if compared to the ravages due to atmospheric dust. 



This preventable destruction is going on to-day, and it has been 

 permitted to go on for ages, without a whisper of information regard- 



