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gear of sufficient power to ensure that the boat can be turned "out against the maximum list under which the lowering of the boats is possible on the vessel on which they are fitted.

"(4) The boat's falls shall be long enough to lower the boat "into the water with safety when the vessel is light. Life-lines "shall be fitted to the davit spans, and shall be long enough to "reach the water when the vessel is light. Hooks shall not be "attached to the lower tackle blocks.

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"(5) Means shall be provided for speedily, but not necessarily "simultaneously or automatically, detaching the boats from the 'falls; the boats placed under davits shall be attached to the falls and kept ready for service; the points of attachment of the boats to the falls shall be sufficiently away from the ends "of the boats to ensure their being easily swung clear of the davits; the boats' chocks shall be of such construction and arrangement as shall be satisfactory to the Board of Trade.

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(6) Where more boats than one are served by the same set "of davits, there shall be provided an approved appliance for lowering the boats in turn and rapidly, and arrangements shall be made to prevent the falls fouling when they are recovered.

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"(7) The Board of Trade may accept in lieu of davits or sets "of davits any other appliance, appliances, or arrangements, "which appear to them at least as effective as davits for placing the boats in the water."

For the ordinary radial davits to be effective and serve the purpose for which they are intended, they must be fitted on the vessel with care and forethought as to the actual requirements. The davits should be placed at such a distance apart as will allow the boat to swing out smoothly and easily, with the falls always hanging plumb.

The relative positions of the head of the davit and the collars or deck sockets can be easily fixed in the drawing office with the aid of paper moulds. It frequently occurs when inspecting the life-saving appliances of a new ship to find that the boat has to be lifted at certain positions when swinging out the davits, in addition to being pushed out, in order to reach the outboard position. A little preparatory work in the office would have obviated the difficulty.

A typical boat stowage arrangement is given in Figs. 238 and 240. The length of the boat is 24 ft., the distance between the davit centres is 21 ft., and that between the davit heads is 18 ft. 9 in. The position of the lifting hooks would therefore be 2 ft. 7 in.

from the intersection of the outside of the planking with the stem, sternpost, or after edge of transom, as the case may be. f... 5:3°

OUTREACH

FIG. 239.-Round bar radial davits for a 24-ft. Class IA lifeboat.

A common practice is to weld a thumb cleat on the davit to take the lead of the fall from the upper block and allow the boat to

swing clear of the falls when launching outboard. It is generally considered that this fitting is dangerous and should be condemned. The boat cannot be raised from the chocks with the fall running over the cleat, consequently when the former is lifted clear it becomes necessary to temporarily lash the falls between the two blocks, to allow the lead to be replaced over the thumb cleat and carried down to the belaying cleat, bollard, or snatch block.

The clump block fitted at the throat of the davit acting in conjunction with a snatch block at the heel, or a combined bollard and sheave as illustrated in Figs. 240 and 241, is a more serviceable and satisfactory arrangement.

Single wire guy ropes are usually fitted to the davits on cargo vessels, but the practice is not recommended and should be replaced by gun-tackle purchases, as being a more reliable method of controlling the davits when launching the boats into the outboard position.

At least four life-lines should be seized to the span between the heads of the davits on all passenger vessels; the length of the lines must be sufficient to reach the light water-line.

It is very essential that particular care be taken to have the hole in the head of the davit, which takes the swivel bolt of the upper block, in a true vertical plane. The operation is usually undertaken when the davit is being forged on the slab in the shipyard. The slightest amount out of the vertical will cause friction and prevent the boat swinging out easily.

The securing nut to the swivel bolt must be recessed, as shown in Fig. 239, to enable a proper bearing being taken on the davit and not on the spectacle which is connected to the spar and guy ropes. Attention should always be given to these fittings to see that they work smoothly and do not jamb.

The socket-davit has long been considered out of date and inefficient. Yet its use is often permitted, and the combination fitted as a part of the statutory equipment of our merchant vessels.

There is one serious limitation to the radial davit, under the present requirements of the Rules for Life-saving Appliances. It is unable to launch a boat over the ship's side against a list, unless it is operated with a mechanical turning out or sluing gear.

The British regulations do not insist on a mechanically-operated davit being fitted to the ordinary cargo vessel, because sufficient seating accommodation is provided in the boats, on either side of the vessel, for the total number of persons on board.

In a foreign-going passenger vessel, i.e. a vessel carrying more than twelve passengers, the davits must be designed to allow the boats to be launched under the condition when the vessel is

assumed to have a list of 15 degrees, the boat being loaded with the full number of persons and details of equipment.

Illustrations of a mechanical apparatus designed for operating

ordinary radial davits against a heavy list, are given in Figs. 227 and 241. The latter shows the details of the worm and screw gear attached to the davit at the deck level. This mechanism is the invention of Mr. George Turnbull, M.I.N.A., of the firm of Messrs. Alfred Holt & Co., Ltd., and has been fitted to quite a number of passenger vessels now in service. The same type of gear can be fitted to socket-davits, where the boat is launched over stanchions and fixed guard rails at the ship's side. Such an arrangement is illustrated in Fig. 242.

Several other gears have been approved by the Board of Trade and adopted by a number of shipowners.

The Pett's Patent Davit Turning-out Gear is controlled by the Quixo Davit Co. of London, and is very similar in principle to the Turnbull patent. The Peninsular and Oriental Steam Navigation Company has recently installed one of their latest passenger vessels with the Quixo Davit Co.'s apparatus.

The Welin Davit and Engineering Co. have patented an arrangement which is operated by a wire rope control, called the planet system," and is designed expressly for manipulating

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