UNDER-GROUND WIRES. 505 



system was at least ten times that of well-constructed overhead lines. 

 By 1850 the earliest of these lines had failed, and by 1853 the entire 

 system was replaced by pole lines. In 1852 asimilar cable was laid 

 in Russia, between St. Petersburg and Moscow ; this worked a few 

 years and then failed. Between 1846 and 1852 many miles of some- 

 what similar cables were laid in France, but, excepting those laid in 

 the sewers of Paris, they universally failed. 



In 1854 quite a number of lead-covered cables were laid in Den- 

 mark, but these were soon obliged to be abandoned in favor of over- 

 head lines. In 1853 the Telegraph Company of England laid down 

 a cable of ten gutta-percha- covered wires, in wooden troughs, along 

 the high-road between London and Manchester, a distance of two hun- 

 dred miles. Although neither expense nor pains were spared in the 

 construction of this line, the cost being comparable with that of the 

 Prussian system, two years had not elapsed before some of the wires 

 ceased to work, and, though these were replaced and workmen kept 

 constantly busy on the line, at the end of seven years the line was 

 wholly abandoned in favor of overhead wires. 



During the same year the Electric Telegraph Company laid down 

 a somewhat similar system between London, Manchester, and Liver- 

 pool, though iron and earthenware pipes were substituted for the 

 wooden troughs. Some of these lines began to fail almost as soon as 

 completed, while others were, by constant repairing and attention, kept 

 working for nearly ten years, when the whole was finally abandoned 

 and overhead lines put up. 



The great trouble with all of these systems, whether in England 

 or on the Continent, was due to water, which found its way to the 

 conductors, and of course destroyed the insulation. It was difficult to 

 handle the wires without abrading the gutta-percha ; and, when safely 

 laid, the gutta-percha was attacked by coal-gas, vegetable growths, 

 and the constituents of the soil. During this time many other shorter 

 lines were constructed, but invariably with the same results. 



In 1855 the French government, having failed in their attempt to 

 use gutta-percha wires, laid down a large number of bare wires in a 

 trench filled in with bituminous compounds. The details of this work 

 were very carefully carried out, and the experiment is of interest 

 because similar plans are constantly being proposed to-day. This sys- 

 tem, costing from eight to ten times that of a thoroughly built pole 

 line, never worked satisfactorily, and soon had to be abandoned. In 

 1858 the administration decided to return to gutta-percha-covered 

 cables laid in lead tubes. The reason of this was, that some of these 

 cables laid in the sewers of Paris, in 1846, were still in good condition. 

 Many miles of this cable were laid, some with the lead pipe laid di- 

 rectly in the earth, some with it drawn again into iron pipes, and some 

 carried through the sewers of the principal cities. Those cables laid 

 directly in the earth soon failed, but those in iron pipes and the sewers 



