adjustment to the davits, falls, or gripes, and thus obviate the necessity of climbing over the boats.

One of the most important factors which governs the successful operation of launching a boat, is the efficiency of the lifting and lowering gear. The practice of simply taking a turn round the davit with the fall when the boat is being lowered into the water, in order to check the speed, is often responsible for accident. There should be a combined bollard and sheave at the heel of the davit as shown in Fig. 241, or a snatch block fitted as shown in Fig. 239. In each case the falls can be taken across the deck, which allows a number of men to speedily lift and easily control the boat and davits.

Additional blocks or fairleads can be fitted to the deck, which will enable a lead to be taken to the winches, and facilities thus provided for hauling up the boats on deck with the least amount of effort.

The question of getting the boats back speedily on board to their stowing positions is not of paramount importance, but it is an item which the chief officer is more than interested in, when boat drills are of such frequent occurrence.

The relative value of the single wire purchase system compared with the multiple purchase is a much debated question.

With a single wire rope the power required for manipulation is much greater. The clutches, brake gear, and the whole construction of the mechanism associated with the control gear must be of heavy scantling, compared with the gear that is associated with a double or treble purchase system.

Care should always be exercised when using new manilla falls, to stretch them well before they are rove through the blocks, afterwards taking the turns out and making the necessary adjustment at the becket to ensure smooth working.

The sizes of falls and blocks have been left to the opinion of the individual shipbuilder, in the absence of any particulars issued to guide him in this important provision. The writer has a personal antipathy to wooden blocks. This opinion may not be shared by others, but these fittings are often of very doubtful design and inferior quality, are very rarely tested, and quickly deteriorate. The cheeks have often been scored and even forced apart during the operation of lowering the loaded boat for the first time, because the size and type were unsuitable for the purpose. You must have weight in the blocks to assist the falls, and this particularly applies to the non-toppling designs. The most successful and useful design of blocks is

considered by many men with sea-going experience to be of malleable cast or wrought iron.

Where more than one boat is served by one set of davits it is most essential that special provision should be made to prevent the lower blocks from " toppling," and the cables from becoming twisted, or what is termed "cable-laid." These difficulties cannot be avoided with the ordinary wood block when the falls are recovered quickly. To obviate the drawbacks associated with the ordinary block many devices have been patented and placed on the market.

The Bulman Patent Boat Block Syndicate of Great Eastern

Street, London, have designed a special apparatus termed the "Bulman" Patent Lifeboat Lowering Gear, which consists of blocks made with the shell or frame extended vertically upwards and formed with a slot or opening extending right across the block above the sheaves. This opening is adapted to receive an end of a bar or rod, preferably rectangular in shape, and which extends across between the two lower blocks attached to the falls, and is thus adapted to prevent the blocks turning over (toppling), or the falls from twisting (cable-laid).

In order that the spar or strongback can be easily detached, if found necessary, a patent tumbler arrangement on top of the block is fitted, which holds the spar securely in position, and at

the same time can be speedily detached by lifting the tumbler.

An illustration of the apparatus is given in Fig. 234.

Several non-toppling blocks are now available for purchase, but very few justify their description, for practically all of them are dependent upon guide plates in some form or another, which do not in any way nullify or remove the inherent tendency of the block to topple, but only prevent it from so toppling by guiding the falls at the expense of a certain amount of chafing. An illustration of the Welin Patent Non-Toppling Block is given in

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FIG. 235.

FIG. 236.

Methods of reeving falls in blocks.

diagrammatic form in Fig. 235. The principle is very simple, the only unusual feature being that the centre sheave of the bottom block is raised, and the blocks are rove in such a way that the fastest running part passes first over the raised sheave, so that the hauling, being always transmitted through this sheave, the bottom block is kept in an upright condition.

Special care must be exercised by the shipbuilder when reeving this patent block, and instructions are issued by the Welin Davit and Engineering Co. for the guidance of shipbuilders. Reference should be made to Fig. 235, and from the position of standing on deck and looking outboard at the side of the block opposite

to the becket, the fall must always be rove from the inboard tread of the bottom sheave over the outboard tread of the top sheave. This will prevent twisting and chafing. Although contrary to accepted practice, these instructions are the outcome of experiments made by the firm, and the falls, with their particular blocks, must be rove as shown; unless the quickest running part passes round the raised centre sheave of the bottom block, the efficiency of the whole gear will be entirely destroyed.

Another method of reeving manila falls through a treble purchase block is shown in Fig. 236.

It is of interest in connection with this portion of the subject, to read from their report the recommendations of the Departmental Committee on Boats and Davits in 1913, in the case where more than two boats are served by one set of davits :—

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(a) A gear must be fitted of sufficient power to turn the boat "out against a considerable list.

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(b) There must be positive control in all positions.

(c) Wire falls should be used, and we recommend either a single or gun tackle purchase.

"(d) The falls should be led to drums fitted with a powerful and reliable hand brake for controlling the lowering of the boat.

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(e) The winding gear must be so designed that it is possible "to adjust the trim of the boat, in order that if the vessel is down 'by the head or the stern, the boat may be lowered into the water on an even keel. This should apply to all cases in "which the winding gear is used.

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"(f) For hoisting the boat and recovering the falls rapidly, there should be a quick-return geared hand-winch to which some system of power might, with advantage, be fitted as an "auxiliary.

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"(g) If the tackles consist of more than a single part, some approved type of non-toppling blocks should be fitted to prevent "the falls from fouling when they are recovered. When the tackles consist of several parts, there is a serious risk that the "lower blocks will capsize. Several types of blocks have been designed which overcome this difficulty with varying success. The simplest arrangement which we have seen is that of weighting the lower blocks below the sheaves and carrying the cheeks of the lower blocks above the top of the sheaves to prevent toppling, and fitting a span between the blocks with a "weight in the centre to prevent the falls cable-laying. We think that this arrangement should prove quite satisfactory

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"with a gun-tackle purchase. It is probable that other types of blocks exist, or will be devised, which will overcome this "difficulty. We refrain, therefore, from recommending any particular type, but suggest that in cases where more than two "boats are served by one set of davits, the Board of Trade should satisfy themselves that reliable non-toppling blocks are fitted." Special precautions should always be taken to stow the falls in such a way that they are ready for use, immediately the necessity arises. To simply dump them down into the boat or let them lie about the deck is to court disaster.

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A number of passenger vessels are fitted with special barrels or tubs, into which the falls are coiled, but the general opinion is that the most serviceable and effective fitting is the reel.

The majority of up-to-date passenger or emigrant vessels are fitted with emergency lighting apparatus, to enable the boat and promenade decks to be well lighted in case of accident to the ship's dynamos. Over each lowering station should be fitted a cluster of lights to facilitate the operation of launching the boats and embarking the passengers. The lighting system may be rendered inoperative by accident; suitable hand lanterns should be stowed in convenient positions as a means of guiding passengers to the boat stations.

Complaint is sometimes received from ships' officers of the unreliability of tarred manila for use as davit falls; instances have occurred when the boat has dropped at one end without the slightest warning being given by the appearance of the manila rope. The cause for the defect may have been in the method of treating the rope, but there is, nevertheless, a very big variation in the quality and price of manila rope falls, and it is a question for consideration whether it would not be advisable to enforce a limiting standard. Further reference is made to this subject in Part X., Section B.

During the recent submarine menace each boat was supplied with two painters, one being fitted with a strop and toggle, and the end led forward and kept belayed to a cleat or other suitable fitting fixed on the deck or bulwark. The purpose of this provision was to enable the boat to be lowered into the water when the vessel was on the move, and permit the boatmen disengaging the lower blocks attached to the falls from the hooks in the lifeboat.

This provision is of special importance where the boats are stowed on the poop, the painters secured to the vessel prevent them coming into contact with the propellers.