ARNOLD HENRY GUYOT. 261 



resonator having but one aperture, which may be formed of a glass ball 

 cut away at one side and cemented to a glass plate having a small hole 

 in the center. When the air ejected from the mouth of the resonator 

 is examined by the method of mixing smoke with it, and then viewing 

 it through slits cut in an open disk, the currents are seen to consist of 

 a series of vortex rings. A variation of this anemometer may be made 

 by taking a card pierced with a hundred holes and placing it between 

 the resonant box and the " mill," when the latter will rotate in the 

 wind which passes through the conical holes. 



The machines of Mayer, Mach, and others, are closely akin to those 

 of Professor Dvorak in design and action. Mr. Edison also has con- 

 trived a phonometer, or instrument for measuring the mechanical force 

 of sound-waves produced by the human voice, in which the vibrations 

 produced in the phonograph-diaphragm by a sound made in the mouth- 

 piece propels a finely-cut ratchet-wheel with considerable velocity. 

 With this device Mr. Edison has "literally accomplished the feat of 

 talking a hole through a deal board." 



■♦«»■ 



ARN^OLD HENRY GUYOT. 



By Pbofessob "W. B. SCOTT. 



THE political disturbances of 1848, injurious as they were to Switz- 

 erland, were directly a great gain to America, for they gave to 

 this country both Agassiz and Guyot, for a long time co-laborers for 

 the advancement of American science and the diffusion of sound learn- 

 ing among the people. " We are led to wonder how much scientific 

 progress would have been delayed in this country if it had not been 

 for the inspiring and co-operating influence of these noble immi- 

 grants." * 



Arnold Hexey Guyot was born near Neuf chdtel, Switzerland, Sep- 

 tember 8, 1807. His early education was obtained at his native town, 

 and it is interesting to note that during his school-life there he was 

 president of the gymnastic club, and one of the best of the school ath- 

 letes. His slight, wiry frame thus received a training in strength and 

 endurance which afterward stood him in good stead when he under- 

 took the immense labors of glacier-study in Switzerland and of mount- 

 ain-surveying in America. On leaving Neuf chatel he went to complete 

 his studies in Germany, attending successively the gymnasia of Stutt- 

 gart and Carlsruhe. At Carlsruhe he was an inmate of the family of 

 the Brauns, and there met his countryman Agassiz, who, with Imhoff 

 and Carl Schimper, was making a vacation visit to his friend Alexan- 



* ii 



Science," Xo. 55, p. 220. 



