However, this remark could very well have referred 

 to a variant of Soemmerring's instrument although 

 Hamel implied that he was speaking of a needle tele- 

 graph. Baron Alexander von Humboldt remarked 

 that in 1832 Schilling had shown an electrical tele- 

 graph (fig. 14) to Czar Nicholas I in Berlin. 



The first contemporary description that we have 

 of Schilling's instruments is a report of a 5-needle, 

 6-wire telegraph that he successfully exhibited at a 

 scientific meeting in Bonn in 1835. This apparatus 

 was a simple one consisting of five needle galvanom- 

 eters. The suspension of each needle had a paper 

 disk marked with a horizontal stripe on one side and 

 a vertical stripe on the other. The bottom end of the 

 suspension rested in a tiny bowl of mercury to damp 

 the oscillations of the magnetic needle under the in- 

 fluence of the current. Schilling also provided an 

 alarm for his telegraph. The code he used seems to 

 have been a binary one — an idea that may have re- 

 sulted from his visit to Gauss in 1833. A demonstra- 

 tion that Schilling made in Vienna in 1836 induced 

 two local scientists to try to set up a telegraphic line 

 along the streets that could be used with Schilling's 

 instruments. Another demonstration that Schilling 

 made to the Russian governm.ent in 1837 led to plans 

 that were prevented by his death in the same year — 

 the Russian government planned to lay an 8-milc 

 submarine cable in an arm of the Bay of Finland near 

 St. Petersburg to connect the fortress of Kronstadt 

 with Peterhof. 



The display of the Russian government at the Paris 

 electrical exhibition of 1881 included an apparatus 

 that was said to have been successfully demonstrated 

 previously by Schilling. The transmitter of this 

 apparatus was a 16-key, piano-type, keyboard con- 

 nected by eight wires to a receiver consisting of six 

 needle galvanometers, plus another galvanometer 

 that was used for a call alarm (fig. 15). 



The Russian government asked M. H. Jacobi to 

 continue Schilling's work in electrical telegraphy upon 

 the latter's death, but Jacobi abandoned Schilling's 

 needle telegraph in favor of another approach.'' 

 Jacobi sought also to reduce the many wires that had 

 been necessary in Schilling's instrument by using a 



simpler binary code. Functionally, Jacobi's first 

 instrument (fig. 16), completed in 1839, was similar 

 to Morse's 1837 instrument. An electromagnet at 

 the receiving station of the Jacobi telegraph was 

 actuated by a key, at a distant point, that closed a 

 circuit. The resulting up-and-down motion of the 

 armature was recorded as a wavy line on a moving 

 plate. This instrument was used in 1839 on an ex- 

 perimental underground line in St. Petersburg that 

 ran from the Winter Palace across the square to the 

 General Staff Building. In 1843 the line was ex- 

 tended from the Winter Palace to Tsarskoe Selo, some 

 15 m.iles away. 



After experimenting with various electrophysiologi- 

 cal telegraphs in the early 1840's, Jacobi invented a 

 dial telegraph in January 1845 that was similar to an 

 instrument that Wheatstone had patented five years 

 earlier; both instruments used pulses of current to 

 actuate a step-by-step mechanism. After the appa- 

 ratus was successfully tested in 1845 during Russian 

 military maneuvers, it replaced the telegraph instru- 

 ment that had been used earlier on the lines between 

 St. Petersburg and Tsarskoe Selo. Another dial tele- 

 graph operated between St. Petersburg and Peterhof. 

 While working with these lines, Jacobi discovered 

 that they acted as condensers and tended to distort 

 the signal transmitted along them. He found that 

 this distortion was more noticeable with underground 

 lines than with overhead lines. 



Jacobi's work in telegraphy must be considered as 

 being of an experimental nature, however, for it was 

 not until 1853, after Siemens and Halske introduced 

 their system., that a semaphore telegraph line be- 

 tween St. Petersburg and Kronstadt was replaced by 

 an electrical one. 



Efforts were also made in England to work out a 

 needle telegraph using a binary code system. In 

 March 1836 William F. Cooke, the son of an English 

 anatomist, attended a lecture at the University of 

 Heidelberg where he saw Prof. G. W. Muncke dem- 

 onstrate an electrical telegraph '^ (fig. 17). Muncke, 

 the chairman of the meeting at Bonn at which 

 Schilling had exhibited his apparatus, had become so 

 interested in Schilling's device that he had sought and 

 obtained permission to have a 3-needle model of this 

 telegraph made. Cooke copied Muncke's model. 



1' M. I. Radovskii, Boris Semenovich lakobi, Leningrad and 

 Moscow, 1953; Akademia Nauk SSSR, Komissiia po istorii 

 fiziko-matematischeskikh nauk, Boris Semenovich lakobi: Bihlio- 

 graficheskii ukazatel, compiled by M. G. Novlianskaia under 

 the editorship of K. I. Shafranovskovo. Moscow and Leningrad, 

 1953. 



18 W. F. Cooke, The Electric Telegraph: Was It Invented by 

 Professor M^heatstone? , London, 1857, 2 vols.; Latimer Clark, 

 "Sir William Fothcrgill Cooke," Journal of the Society of Telegraph 

 Engineers, 1879, vol. 8, pp. 361-397. 



286 



BULLETIN 228: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 



