File:Bulletin (1961-1962) (20235181100).jpg

Title: Bulletin
Identifier: bulletin228smit (find matches)
Year: 1961-1962 (1960s)
Authors: Smithsonian Institution; United States. Dept. of the Interior; United States National Museum
Subjects: Science
Publisher: Washington, Smithsonian Institution Press, (etc. ); for sale by the Supt. of Docs. , U. S. Govt Print. Off
Contributing Library: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library
Digitizing Sponsor: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library

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Figure 65.—Colton's electric locomotive. (USNM iSi^yy; Smith- sonian photo 4yo^8-B.) hour. A few months later, his motors had reached an estimated 8 to 20 horsepower, and on a 39-minute trip from Washington to Bladensburg had driven a locomotive at a top speed of 19 miles per hour.^"* However, the trip was so rough the diaphragms of the 50 Grove cells—required for each motor—and the in- sulation in the motors broke down. Page's funds were exhausted by then, and he made no further experi- ments. Another of these successful early inventors was Moses G. Farmer of Dover, New Hampshire. Farmer devised an electric motor in 1846 that in its first public exhibition in July 1847 drove an electric train (fig. 70) of two cars on an 18-inch-gauge track."" Farmer had other exhibitions in New England later in the year; but his exhibitions were not financially successful, so he turned to the field of telegraphy. 108 Walter K. Johnson, "Report on Professor Page's Electro- Magnetic Locomotive," American Journal of Science, 1851, vol. 11, pp. 473-476; "Professor Page's Electric Engine," Scientific American, 1854, vol. 9, p. 394. Page patented his electric motor (U.S. Patent 10480) on January 31, 1854. "" Electricity and Electrical Engineering, 1893, vol. 4, p. 279. By midcentury the general public was becoming increasingly aware of the possibilities of electrical power. Part of the increase in public attention resulted from the awarding of prizes for the invention and use of electric motors. Beginning in 1844 the French instrument-maker G. Froment constructed many motors (such as the one shown in fig. 69). Napoleon HI awarded him the Volta prize in 1857 for having a shop completely run by electric motors."" Sjziren Hjorth, of Denmark, developed a motor (fig. 71) that was shown at the Great Exhibition of 1851 in London, where it won considerable attention as well as a prize. By this time two basic forms of the electric motor had been developed. One of the basic forms was a reciprocating engine, where an armature was pulled into a solenoid, as in Page's motor, or an armature hinged at one end was pulled down by an electro- magnet, as in Clarke's motor. Linkages changed the linear motion to a rotary one. The other basic form >'» Cosmos, May 8, 1857, vol. 10, pp. 495-497; Les Mondes, May 7, 1863, vol. 1, pp. 337-338. 268 BULLETIN 228: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY

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