the needed article. I had also to manufacture some brass wire to make the necessary springs for the circuit-closer of the branches. Finally after a great deal of pains and labor, by the latter part of March the line was completed and entirely ready for immersion. I had made from Mr. Waldron several inquiries about the location of the lines, the nature of the bottom, the strength of the current, the depth of the water, &c. His opinion was that the place and was confident of the result. Much to my regret we made three unsuccessful attempts to lay the cable. Its multiple elements, in addition to the necessary lines to buoy and anchor the torpedoes, were impossible to be managed in the midst of such a current so as to keep the proper distance between the different parts. During out last trial 500 feet which we had cast off were in two hour's time carried away by the tide 1 1/2 miles from its original position (the whole of it being in a confused mass). I accordingly, in several reports to Major Harris, related the facts connected with our operations, concluding against any further attempts in that locality. I profess a great respect for Dr. Cheves' plan; it is well combined, and will certainly work to satisfaction in a smoother place than our bay, where the different branches and lines will retain their position and avoid the friction and its destructive effects.

Telegraph lines.-While Dr. Cheves' cable was in progress we received an order from General Ripley to run a submarine cable for telegraph purposes between Forts Sumter and Moultrie, which operation was successfully performed on the 10th of March last. Shortly after a portion of submarine cable was also laid in the Steamboat Channel between Sumter and Johnson in place of the old one made by Dr. Cheves, and connecting the air line through the Middle Ground, the injuries frequently sustained by the old cable interrupting most the time the transmission of messages to and from Fort Sumter. Since the air line was completely removed and a submarine cable laid to Fort Johnson.

Big torpedoes.-Few days before the attack on the forts a boiler, 18 feet long, 3 feet in diameter, containing 3,000 pounds of powder, was laid by General Ripley's order in the main Ship Channel about 1 mile off Fort Sumter and half a mile opposite Fort Wagner. The following sketch will show the mode of fastening and anchorage selected for the same.

The boiler was secured by two iron straps on two longitudinal pieces 10 by 10 and 20 feet long, united by six transversa pieces 10 by 10 and 10 feet long. Four anchors of a hemispherical shape, weighing 3,000 pounds apiece, were set and secured at each corner of the frame.