check, by the application of what were known as self-releasing brakes. These were the invention of Mr. Appold, of London, a gentleman of fortune, but with a strong taste for mechanics, which led him to spend his time and wealth in exercising his mechanical ingenuity. These brakes were so adjusted as to bear only a certain strain, when they released themselves. This ingenious contrivance was applied by Mr. Everett to the paying-out machinery. The strength of the cable was such that it would not break except under a tension of a little over three tons. The machinery was so adjusted that not more than half that strain could possibly come upon the cable, when the brakes would relax their grasp, the wheels revolve easily, and the cable run out into the sea without a jar. The paying-out machine, therefore, we are far from claiming as wholly an American invention. This part of the mechanism was English. The merit of Mr. Everett lay in the skill with which he adapted it to the laying of the Atlantic cable, and in his improvements of other parts of the machinery. The whole construction, as it afterwards stood upon the decks of the Niagara and the Agamemnon, was the product of English and American invention combined. The engineers, who now saw it for the first time, were delighted. It seemed to have the intelligence of a human being, to know when to hold on, and when to let go. All felt that the great difficulty in laying the cable was removed, and that under this gentle manipulation it would glide easily and smoothly from the ship into the sea. While these preparations were going on in London, the Niagara, which did not leave New York till the ninth of March, arrived at Plymouth, under command of Captain Hudson, to take on board her share of the cable. Both ships had discharged their burden at Keyham Docks, where the precious freight was passed through a composition of tar and pitch and linseed-oil and beeswax, to preserve it from injury, and had been coiled under cover to be kept safely through the winter. The Agamemnon was already at Plymouth, having been designated by the Admiralty again to take part in the work, though under a new commander, Captain George W. Preedy, an excellent officer. The place of the Leopard was taken by the Gorgon, under command of Captain Dayman, who had made the deep-sea soundings in the Cyclops the year before.