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A Light-Ship Electrically Connected With the Shore. (From the Times, 20th March, 1894.)

THE Royal Commission on Electrical Communication with Light-houses and Light - vessels recommended that five light-vessels be immediately connected with the shore by a telegraphic cable, viz., the Goodwin, at the north end of the sand; the Kentish Knock, at the Thames entrance; the Shipwash, off the Suffolk coast; the Hasborough, off the Norfolk coast; and the Scarweather, off the northern shore of the Bristol Channel, to the southward of Swansea Bay. From the experience gained by the experimental connection of the Sunk Light-vessel with the shore for a continuous period of eighteen months, it has been found that there is no serious difficulty in main- taining the electric connection between a light-ship and the shore. Bat there are light-ships and light-ships—some moored in quiet waters where turbulent seas are unknown and the vessels ride easily; others where they are subjected to con- tinual jumping over short waves; others where real ocean toilers are experienced, causing the vessel at times to be lifted up on the crest of a huge wave and to be dropped into the following depression. In the case of the Sunk Light-ship very heavy seas were seldom or never experi- enced, the bottom was even, and the 11 miles of electric cable lay comfort- ably enough on the sea-bed all the way to Walton-on-the-Naze. A light-ship is ordinarily moored with a single chain cable, the links being of 1 -in. iron, attached to a mushroom anchor weighing from 2 to 3 tons. The vessel is never allowed to pull taut upon her anchor; a quantity of the chain cable is allowed to lie on the bottom, and as the ship rises to a wave she pulls at the loose chain, the weight of which is sufficient to hold her and yet gives sufficiently to enable her to surmount the waves. In bad weather a greater scope of chain is veered out, and on the judicious management of the cable mainly depends the secure riding of the vessel. During the last thirty years no light-ship in the Trinity House service has broken adrift even in the worst weather. In addition to the riding of the vessel over broken water, she swings with the tide, going round sometimes one way and sometimes another. It will, therefore, be understood that these some- what complicated movements of the light- ship with a heavy chain cable pendent from her bows and much loose chain on the bottom constitute serious difficulties in the way of leading out from the light- ship another cable of much less strength in such a manner as to avoid entanglement with the mooring chain. Many projects have been put forward for accomplishing this, but the large majority of the pro- jectors have failed to realise the difficulties of the problem. The plan adopted in the case of the Sunk Light-ship was on the principle that the electric cable should be so led away that it could not get entangled with the mooring chain. To effect this two mushroom anchors were laid a considerable distance apart, to each of which was attached a sufficient length of chain cable. These lengths of chain were brought together and joined to a large swivel, and from the top of the swivel a single veering chain passed into the light- ship through the hawse pipe. This swivel, designed and patented by Mr. F. Bedwell, of the Telegraph Construction and Main- tenance Company, had a circular hole through its centre, and a light electric cable from the vessel was carried through this hole and spliced on to the main electric cable, which ran in quite a different direction from that of either of the two arms of mooring-chains and anchors. One great necessity appeared to be that the swivel should be always kept above the sea bottom, so as to insure that the telegraph cable was kept free from contact with the mooring chains.

After some experience with this plan, of course involving some failures and fractures, it was ultimately found practic- able to keep the electric cable intact without interfering materially with the safe and secure riding of the ship. As she swung round with the tide the light electric cable was passed over by hand, when necessary, to the other side.

It is now satisfactory to chronicle the fact that another and a most important light-ship has just been put in electric IST AUGUST, 1894.] THE LIFE-BOAT.

775 communication (we hope permanently) with the shore. The Kentish Knock Light-ship is in every sense an outside vessel, and is moored in about 12 fathoms at low water. She is 18 miles from the nearest land, and marks the sandbank from which she takes her name in the sea approaches to the river Thames. She is exposed to heavy seas, especially when the wind is easterly. The nearest land is the North Foreland, and it is from the post- office at Kingsgate that the submarine cable is now taken to the light-ship.

Owing to the much more exposed position of this vessel than that of the Sunk, it has been necessary to adopt greater precautions in respect of the moorings.

Instead of two arms of moorings there are four—i.e., there are four mushrooms placed in relation to the ship's position N.E., S.E., S.W. and N.W. Four chain cables, each about 210 fathoms long, from these mushrooms are brought to- gether at a centre swivel (Bedwell's patent) and connected to the four outer loops of the swivel, and from the swivel two chain bridles pass into the ship.

The swivel has to be kept about 6 fathoms above the sea bottom, and thus it will be seen that the vessel has to carry a great weight from her bows. The laying of these moorings and fixing the ship to them has been carried out, under the directions of the Elder Brethren of the Trinity House, by the Superintendent of the London District, Mr. Hattersley, and Mr. Beading, the master of the Trinity steamer Vestal. All things being ready for the reception of the electric cable, the Post Office authorities were informed, and the cable-ship Monarch was despatched to lay the submarine cable from Kingsgate.

Under the personal directions of Captain Lumsden, Submarine Superintendent of the Post Office, and other officers of the Department, this work was quickly done and the cable brought across the em- bouchure of the Thames to the Kentish Knock. A lighter cable was then reeved through the central hole in the swivel and taken inboard, the other end being spliced on to the main cable, and at 3 o'clock last Wednesday afternoon a message was sent through from the light- ship to the General Post Office, to the effect that the first of the permanent light-ship cables had been successfully laid and communication established. How long the communication will be main- tained experience only can determine, but there is good reason to hope that the real difficulties have been practically overcome, and that we need not expect any prolonged failure in keeping up the connection. But, on the other hand, it must be borne in mind that the light-ship has an enormous weight from her bows, that .to a certain extent she is pinned down, and cannot have the freedom of a vessel riding with only a single chain cable. Whether this will be in any way prejudicial to the safety of the ship in the worst weather remains to be seen, but the master will always be able, in case of danger, to let the swivel drop on to the bottom, and so insure the ship's safety. Such a proceed- ing, however, would most likely result in the breaking of the electric cable.

The Trinity yacht Irene, with Sir Sydney Webb, Captain Vyvyan and Sir Leopold M'Clintock, tested the commu- nication on their return journey after escorting Her Majesty to Flushing.

The Trinity House and Post Office are working together in much harmony in this matter, and are now giving their attention to the connection of the Goodwin Light-ship with the shore..