SKETCH OF PROFESSOR HELMHOLTZ. 231 



percent, of its own weight, and, if we adopt, for the normal product to 

 inject, f of tannic acid and \ of tannate of protoxide of iron, the cost 

 would amount to from yfo to j-g-o of a franc, making, in all, an expense 

 of -f^Q of a franc per slee^^er. 



Trials of this process are at this moment in course of execution 

 upon a grand scale, by the Railway Company of the East, and the 

 Administration of the National Telegraphs, with the authority and 

 cooperation of the Minister of the Interior. — Comi^tes Re^idus. 



SKETCH OF PEOFESSOE HELMHOLTZ. 



By G. a. F. van EHYN. 



&EEMANY assembled in 1869 her greatest savants to celebrate 

 the centenary anniversary of the birth of Alexander von Hum- 

 boldt, her greatest dead. The highest honor of this occasion was 

 bestowed on Prof. Helmholtz, who delivered the opening oration. 

 He reviewed the progress made in the natural sciences with special 

 reference to the labors of German students, and said : " In Germany 

 there has always been a greater fearlessness of the consequences result- 

 ing from speaking the whole truth than anywhere else. The eminent 

 savants of England and France are still obliged to bow to the dictates 

 of social and ecclesiastical prejudices, and, when they speak openly, 

 they do it to the injury of their social standing. Germany is bolder ; 

 she confides in what has never proved false — that the whole truth is 

 the best remedy for the evils of truth imperfectly stated." 



The Academy of France lent new force to his statement by refus- 

 ing to elect him a corresponding member, on account of the advanced 

 ideas connected with his name. A French critic rebuked his country- 

 men for hesitating to bestow on Helmholtz, the greatest living physi- 

 cist of this century, so slight an honor, with the remark : " For his 

 glory nothing is wanting ; but he is wanting for ours." The Acad- 

 emy elected him in the following year. 



HERMAjra- LuDwiG Ferdinand Helmholtz was born August 31, 

 1821, in Potsdam, the Prussian Versailles, the town of palaces, which 

 gave birth to Alexander von Humboldt, and holds the ashes of Fred- 

 erick the Great. His father was a teacher at the gymnasium in Pots- 

 dam, and a man possessed of a great store of knowledge. Under his 

 guidance Hermann was soon prepared to enter the institution, where, 

 as usual, too much Latin and Greek was taught for his youthful taste. 

 He was, however, not permitted to shirk any of his studies, and, with 

 that patient perseverance which is a dominant trait in his character, 

 he ran through the whole curriculum of the gymnasium before he had 



