SOME RECENT TRIUMPHS 



antiseptics; he introduces friendly insects to prey 

 on insect pests; he irrigates or surface-tills or grows 

 cover crops in accordance with a good understanding of 

 the laws of capillarity as applied to water in the earth's 

 crust. In barnyard and dairy he applies a knowledge 

 of the chemistry of foods in his treatment of flock and 

 herd ; he ventilates his stables that the stock may have 

 an adequate supply of oxygen ; he milks his cows with 

 a mechanical apparatus, extracts the cream with a 

 centrifugal "separator," and churns by steam or by 

 electric power. 



In the affairs of manufacturer and transporter of 

 commodities, methods are no less revolutionary. 

 Steam power and electric dynamo everywhere hold 

 sway; trolley and electric light and telephone have 

 found their way to the most distant hamlet; electri- 

 cians and experimental chemists are searching for new 

 methods in the factories; artificial stone is competing 

 with the product of the quarries; artificial dyes have 

 sounded the doom of the madder and indigo industries. 



And yet it requires no great gift of prophecy to see 

 that what has been accomplished is only an earnest 

 of what is to come in the not distant future. In every 

 direction eager experimenters are on the track of new 

 discoveries. Any day a chance observation may open 

 new and important fields of exploration, just as Hall's 

 observation about the power of cryolite to absorb 

 aluminum pointed the way to the new aluminum 

 industry; and as BirkelanoVs chance observation of 

 the electric arc in a magnetic field unlocked the secret 

 of the unresponsive nitrogen. It will probably not 



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