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In the East Indies a line of telegraph has been laid down, a;;d is now in working order between Calcutta and Kedgeree, a distance of 72 miles. This has been done by a Dr. O. Shaughnessy, an Irish gentleman. It is now proposed by the Governor-General of India, Lord Dalhousie, to unite all the important places in the British possessions in that country by electric cords. This will embrace lines of 8,800 miles long. The line which has been constructed differs entirely from any of our lines in America. The conductor (a wire with us,) is laid part of the way under ground, in a cement of melted rosin and sand, and is a five-eighth of an inch iron rod.' Part of the way it is carried over ground on bamboo poles, fifteen feet high, coated with coal, tar, and pitch, and strengthened at various distances by posts of saul wood, teak, and' iron wood from America. The bamboo posts are found to resist storms which have uprooted trees the growth of centuries. Though the . bamboo soon decays, yet its amazing cheapness makes the use of it more economical than that ot more durable and more costly materials. The branch road from Bish- lopore to Moyapore passes through a swamp ; the country is little less than a lake for five months; the conductor runs on foot paths between the island villages, and for some miles crosses rice swamps, creeks and jeels on which no road or embankment exists. The most diffcult and objectionable line was selected to test the practicability of carrying the conductors through swampy ground, and it has been perfectly succcessful. The Hul- dee river crosses the Kedgeree line half-way, and “aries in breadth from 4,200 to 5,800 feet. A gutta percha wire, secured in the angles of a chain cable, is laid across and under this river, and this chain is found to afford perfect protection from the grapnells ot the heavy native boats which are constantly passing up and down. The advantages of the iron rod as a substitute for the wire, are stated to be complete immunity from gusts of wind, or ordinary mechanical violence ; if accidentally thrown down, they are not injured, though passengers, bullocks, buffaloes, and elephants may trample on them: they are not easily broken or bent ; owing to the mass of metal, they give so free a passage to the electric currents, that no insulation is necessary ; they are attached from bamboo to bamboo without any protection, and they work without interruption through deluges of rain; the thickness of the wire allows of their being placed on the post, Without any occasion for the straining and winding apparatus, whereas the tension of wires exposes them to fracture, occasions expense in construction, and much difficulty in repairs ; the thick rods also admit of rusting to take place, without danger, to an extent which would be fatal to a wire. On several occasions, one village forge, carried by two coolies, has been found sufficient for welding a mile of rods in a working day. The rods, moreover, are not likely to be injured by crows or monkeys. Swarms of kites and crows perch on the lines through the swamps but they cause no harm; the correspondence flies through their claws without interruption, though on one occasion a flash of lightning struck the wet rod, and killed some scores of them. The importance of this discovery of the superiority of rods over wire will be fully appreciated in a country like India, where the line must often run through a howling wilderness, tenanted by savage beasts, or more savage men. The lines must therefore protect themselves, and this is secured by the use of thick rods.
