pany felt that it was in a sufficiently strong position 

 to take action against Western Union's entry into the 

 field of telephony and accordingly brought suit against 

 an agent of one of Western Union's subsidiary com- 

 panies. After two years spent collecting testimony 

 and preparing to defend this case, the Western Union 

 lawyer recominended that it be settled out of court. 

 In exchange for agreeing not to enter the telegraph 

 business and for giving 20 percent royalties to West- 

 ern Union for 17 years, the Bell people obtained full 

 rights to all telephone patents held by Western Union 

 (including those of Gray, Dolbear, and Edison), as 

 well as the right to purchase Western Union's 56,000 

 telephones and its associated telephone exchanges. 

 This settlement and the Supreme Court decision of 

 1887 gave the Bell company control of the telephone 

 business for the remainder of the duration of the Bell 

 patents. 



At first the telephone simply replaced the telegraph 

 in private-line telegraph circuits that already existed.^' 

 For instance, in May 1877 E. T. Holmes of Boston 

 showed how the new instrument might be connected 

 to a telegraph burglar alarm system. Telephones 

 were connected to the central station of the system 

 during the day, and telegraphs were connected at 

 night. However, Holmes' demonstration lasted only 

 a few weeks, for problems were involved in connect- 

 ing many telephones with one another that could 

 not be handled in a telegraph central station. The 

 first telephone switchboard that was used for regular 

 commercial service was installed in New Haven in 

 January 1878. In the same year Thomas A. Watson 

 added to the telephone system the polarized ringer 

 (fig. 78), a device for signaling between stations and 

 calling the operator. In 1879 H. L. Roosevelt 

 patented the automatic switch (fig. 79) that notifies 

 the operator when a telephone is in use. The re- 

 mainder of the century brought many changes in 

 the telephone system, including the multiple and 

 the common battery switchboard, as well as some 

 experimental beginnings of automatic switching. 



In the 1880's there was a great increase in the 

 number of telephones. The area interconnected by 

 telephone also increased. This increase in the area 

 covered by telephones was made possible by the 

 metallic circuit and by the introduction of hard copper 



Figure 79. — Patent drawing of 

 Roosevelt's telephone switch. 

 From U.S. patent 215837 (May 

 27, 1879). 



wire for use in telephone lines. °^ In 1880 and 1881 

 the telephone company started replacing the single 

 wire and ground circuit inherited from telegraphy 

 with a twisted pair of metal conductors. About the 

 same time a hard copper wire began to be used. 

 This copper material was a more efficient conductor 

 of electricity than the iron and steel wires that had 

 been used in long spans up to this time. These 

 new improvements made it possible to join New 



'1 Frederic L. Rhodes, Beginnings of Telephony, New York, 

 1929, pp. 147-188. «2 Ibid., pp. 66-136, 



PAPER 29: DEVELOPMENT OF ELECTRICAL TECHNOLOGY IN THE 19TH CENTURY: II 



331 



