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The Great Eastern took on board seven or eight thousand tons of coal to feed her fires, a prodigious quantity of stores, and a multitude of live stock which turned her decks into a farmyard. The system is constructed as follows: Eight wrought-iron pipes, three inches in diameter, are laid side by side in two rows, about four feet below the surface. The present complete system, as used between Liverpool and Manchester, was constructed as follows: Iron or stoneware pipes were laid from one to two feet below the level of the road-side with flush-boxes coming to the surface every two hundred yards. As the two lines constructed in Boston are short, only about one quarter of a mile each, it was deemed best to use single-line circuits, hoping that the induction and retardation on so short lines would not be serious. The route was especially selected through a low and marshy section of country, so that the pipes were almost constantly filled with water-this being the best possible condition for the preservation of the gutta-percha. It was due to the brilliant promise he displayed, as much as to the influence of his father, that at the age of twenty-two he found himself wearing the gown of a learned professor in one of the oldest Universities in the country, and lecturing to the class of which he was a freshman but a few years before.

In answer, I propose to describe briefly what has been done in this direction in European cities, then to look at some experiments lately made in this country, and thus to show how far such a plan is and how far it is not practicable. The first clear message was sent through the cable on 13 Aug., and it continued working till 20 Oct., during which period 732 messages passed through the cable, and then it finally broke down ; probably the insulation had given way owing to the excessively strong currents used at first in working it. Though this cable so soon broke down, the mere fact that many successful messages had been sent through it showed that the problem was one which could be solved. As early as 1859, Sir William sent out to the Red Sea cable a piece of apparatus with this intent. Sir William Thomson has been all his life a firm believer in the truth of Christianity, and his great scientific attainments add weight to the following words, spoken by him when in the chair at the annual meeting of the Christian Evidence Society, May 23, 1889:-'I have long felt that there was a general impression in the non-scientific world, that the scientific world believes Science has discovered ways of explaining all the facts of Nature without adopting any definite belief in a Creator.

Subsequently Sir Charles Bright supervised the laying of submarine cables in various regions of the world, and took a leading part as pioneer in other developments of the electrical industry. The cost of one wire by itself is vastly larger than where many are run together, the cost of the pipe and for laying being not much greater for fifty wires than for one, and the cost of single wire cables being greater per mile of wire than multiple wire cables, so that the expense of putting such a system as one of our telephone exchanges entirely under-ground would place the cost of the instruments entirely out of reach of the subscribers. It is also demonstrated that the cost, even when a large number of wires run side by side, is enormously increased. As the paper moves over the pulleys a delicate hair line is marked, straight when the siphon is stationary, but curved when the siphon is pulled from side to side by the oscillations of the signal coil.

Telephone wires, electric-light wires, and a large majority of telegraph wires in European cities are, however, as in America, carried over house-tops or on poles. It consists of seven copper wires, each coated with two layers of gutta-percha and two of Chatterton's compound, and the whole covered with an armor of galvanized-iron wires. The cable most generally made in Paris consists of seven gutta-percha-covered wires laid into a cable covered with tarred hemp and drawn into a lead pipe; this pipe is fastened by hooks to the side-wall of the sewer. The distances within this city are so short that neither induction nor retardation has to be considered in the telegraph wires. We have seen that in Paris the retardation and induction are both obviated by the use of double and twisted wires in metallic circuit. In Paris, all the wires are carried in the sewers under-ground. There are several thousand miles of wire in the sewers of Paris, and the cost of the gutta-percha-covered cables is about $140 per mile of wire, or about five times the cost of a pole line to do the same work. In any other city than Paris, the above figures would be very greatly increased by the cost of under-ground piping and chambers to contain the cables.

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