Figure 59. — Clarke's electric locomotive. 

 From Sturgeon's Annals of Electricity, 1840, 

 vol. 5, p. 304. 



Figure 58. — Clarke's motor. From Sturgeon's 

 Annals of Electricity, 1840, vol. 5, pi. i, fig. 3. 



London in August 1838, one of Davenport's motors 

 drove a small electric train of several carriages with a 

 total weight of 70 to 80 pounds at a speed of 3 miles per 

 hour.'^ Davenport tried to use his rotating motor to 

 drive a Napier printing press that printed his paper 

 "The Electro-Magnet," but the press required an 

 engine from 1 to 2 horsepower, and he did not succeed 

 in building such a motor until 1840.^* Success came 

 to Davenport with his development of a reciprocating 

 engine based on a "sucking coil" that he had begun 

 working on in 1838. Davenport built over 100 motors 

 in his lifetime, but lack of financial backing and his 

 inability to obtain an inexpensive source of power 

 defeated him. 



By the early 1840's there were a number of inventors 

 of electric motors. In 1839 Robert Davidson of 

 Edinburgh constructed an electric motor that had 

 enough power to turn articles on a lathe or to drive a 

 small carriage (fig. 56). Three years later, Davidson's 

 motor could drive a carriage weighing about 6 tons 

 for a mile and a half at a speed of 4 miles per hour.^'' 



9» Mechanics' Magazine, London, 1838, vol. 28, pp. 321-323; 

 vol. 29, pp. 95-96, 115, 166-168, 170-172. 



86 Ibid., 1840, vol. 32, pp. 407-408. 



" Ibid., 1840, vol. 33, p. 92; "Electro-Magnetic Locomotive 

 Carriage," Stuvgeon's Annals of Electricity, 1842, vol. 9,234-235; 

 "The Earliest Electrical Railway," Electrical World, 1890, vol. 

 16, pp. 276-277. 



Figure 60. — Wright's motor. From Sturgeon's 

 Annals of Electricity, 1840, vol. 5, pi. 3, fig. 4. 



A drawing of this 1842 motor is shown in figure 57. 

 In 1840 Uriah Clarke'* devised a reciprocating engine 

 (fig. 58) and then applied it to a 100-pound miniature 

 railway (fig. 59). Thomas Wright '^ reported on a 

 reciprocating engine (fig. 60) that Clarke promptly 

 criticized as impractical. William Taylor patented an 

 electric motor '"'' (fig. 61) in 1840. James Joule'" 

 worked on several different models of electric motors, 



's Uriah Clarke, "Description of an Electro-Magnetic 

 Engine," Sturgeon's Annals of Electricity, 1840, vol. 5, pp. 33— 

 34; "Description of an Electro-Magnetic Locomotive Carriage," 

 Sturgeon's Annals of Electricity, 1840, vol. 5, pp. 304-305. 



»' Thomas Wright, "On a New Electro-Magnetic Engine," 

 Sturgeon's Annals of Electricity, 1840, vol. 5, pp. 108-110. 



i»» British Patent 8255, November 2, 1839. 



i"' James Joule, "Description of an Electro-Magnetic Engine," 

 Sturgeon's Annals of Electricity, 1838, vol. 2, pp. 122-123; 1839, 

 vol. 3, pp. 437-439; 1840, vol. 4, pp. 203-205. 



PAPER 28: DEVELOPMENT OF ELECTRICAL TECHNOLOGY IN THE 19TH CENTURY: I 



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