THE CONQUEST OF TIME AND SPACE 



street-car lines all over the country that there was an 

 appreciable depression in the market prices of such 

 horses. 



The importance of this method of transportation is 

 shown in the fact that between the years 1873 and 1890 

 more than a thousand different patents directly con- 

 nected with the operation of cable roads were issued by 

 the United States Patent Office. But by 1890 electric 

 traction had become practical, and the issuing of patents 

 for cable lines ceased as abruptly as it had begun. 

 Before the close of the century practically every im- 

 portant cable line in the United States had changed its 

 motive power to electricity. Thus in a brief quarter 

 of a century this method of street-car traction had come 

 into existence, revolutionized all hitherto known meth- 

 ods, and become obsolete. 



EARLY SELF-CONTAINED SYSTEMS 



In most of the earlier attempts to solve the problem 

 of electrical propulsion the motor vehicles were con- 

 structed on a self-contained plan — that is, the power 

 was generated on the locomotive itself, just as in the 

 case of the steam locomotive. As early as 1835 Thomas 

 Davenport, a blacksmith of Brandon, Vermont, con- 

 structed such a motor operated by cells, and built a 

 small circular railway in Springfield, Massachusetts, on 

 which he drove this electro-magnetic engine. This 

 miniature railroad was of no practical importance, 

 but it has the distinction of being the pioneer electric 

 road. 



[178] 



