Now it may be fairly concluded, from our experience of the “Atlantic Telegraph Expeditions” in 1857, 1858, and 1865,--That a submarine telegraph Cable can be laid between Ireland and Newfoundland, because it was actually done in 1858. That messages can be transmitted through a Cable so laid, because 271 messages were sent from Newfoundland to Valentia, and 129 messages from Valentia to Newfoundland, in 1858. That the insulation of a Cable increases very much after its submersion in the cold deep water of the Atlantic, and that its conducting power is considerably improved thereby. That the steamship Great Eastern, from her size and constant steadiness, and from the control over her afforded by the joint use of paddle and screw, renders it possible and safe for her to lay an Atlantic Cable without regard to the weather. That the egress of a Cable in the course of being laid from the Great Eastern may be safely stopped on the appearance of a fault, and with strong tackle and good hauling-in machinery, the fault may be lifted from a depth of over 2000 fathoms, and cut out on board the ship, and the Cable respliced and laid in perfect condition. That in a depth of two miles a Cable can be caught at the bottom, because four attempts were made to grapple the Cable in 1865, and in three of them the Cable was caught by the grapnel. The paying-out machinery, constructed by Messrs. Canning and Clifford, and used on board the Great Eastern in 1865, worked perfectly, and can be confidently relied on for laying Cables across the Atlantic. With the improved telegraphic instruments, for long submarine lines, of Professor W. Thomson and Mr. Varley, a speed of more than eight words per minute can be obtained through such a circuit as the Atlantic Cable of 1865, between Ireland and Newfoundland; as the amount of slack actually payed-out did not exceed 14 per cent., which would have made the total Cable laid between Valentia and Heart’s Content less than 1,900 miles. The Cable of 1865, though capable of bearing a strain of 7 tons, did not experience more than 14 cwt. in being payed-out into the deepest water of the Atlantic between Ireland and Newfoundland. There is no difficulty in mooring buoys in the deep water of the Atlantic between Ireland and Newfoundland; a buoy, even when moored by a piece of the Atlantic Cable itself which had been previously lifted from a depth of over 2000 fathoms, has ridden out a gale. More than four miles of the Atlantic Cable have been recovered from a depth of over two miles, and the insulation of the gutta-percha-covered wire was in no way whatever impaired, either by the depth of water or the strains to which it had been subjected by lifting and passing through the hauling-in apparatus.