SHIP BUILDING. 47 



as shown in^^. 13. A plan of convenient cross-bolting is shown mjig. 14. 

 Here especially no unseasoned timber is to be used. Fig. 27 shows a longi- 

 tudinal section of an English 120-gun ship ; Jigs. 18, 19, plans. The manner 

 in which merchant ships are built is by no means suited to the present 

 demands of ships of war. The joinings of their timbers and frames and the 

 arrangement of their materials are of such a character, that while one half 

 forms a kind of arch, the other half and the connecting pieces are only 

 loosely put together, and are secured by the planks instead of giving to 

 them a firm support, as they should do. Such vessels can never have the 

 same stability as if all the parts were connected in the manner of an arch, 

 according to the plan proposed by Seppings. 



There is a great defect in the manner hitherto adopted of joining the 

 separate parts of the same timber. This is usually done by the addition 

 of a third piece, a, shaped like a wedge {pi. 9, Jig. 20). More than 550 

 such pieces are used in a 74-gun ship, and no fewer in an East India 

 merchantman of 1200 tons. On thoroughly overhauling a vessel for 

 repairs, not one of all these pieces is found to be in good order, and 

 the}^ moreover, will be found to have damaged the timbers to which 

 they are applied. Besides, the timbers cannot be bent sufficiently with- 

 out destroying their fibres. There is a great loss of material also by 

 cutting off the corners of the timbers which are to be connected by the 

 wedge-piece. No doubt, these pieces were first made use of when none but 

 too short or imperfect timber was to be had {Jig. 21) ; but the requisite 

 curvature can be obtained by a peculiar arrangement without such a great 

 loss of material. The frames of merchantmen, before they are joined together, 

 are partly shown in Jig. 24, and too often, in consequence of bad work, the 

 parts are often not accurately fitted to each other, nor to the timbers with 

 w^hich they are connected. There are, moreover, many defects in the con- 

 nexion with the keel. In order to obviate all these difficulties, Seppings 

 proposed the combination {Jigs. 22 and 23), in which the connecting 

 timbers are a little shorter and not so much bent, nor so much cut through 

 the fibres. The connexion is also made firmer by using a pin (I) instead 

 of the wedge-piece. Another advantage, finally, is that when the ship 

 grounds the timbers give the whole structure more firmness and support, as 

 is shown by the dotted line at the bottom of Jig. 23. In regard to the 

 general security of the arrangement, it will be seen from Jigs. 25 and 15 

 that the timbers regularly cross the keel, and that the frames in the vicinity 

 of the lower deck at K compose a firm ship's body, while only a few courses 

 of planks, L, are applied at the joining of the timbers in order to give 

 greater strength at these places. The other inside courses of planks may 

 be left out, and instead of them double upright pales placed between the 

 planks and the timbers, as at M. This gives more room for stowage. 

 Water-ways, N, between the planks conduct the water to the pumps, which 

 now reach the water themselves, and hence there may be standing water 

 in the space, as all the gutters can be easily cleaned. The timbers which 

 (as in pi. 9, Jig. 25) are fastened directly to the sides require no knees, or 

 only very small iron ones. Fig. 16 shows, in the part P, the old system of 



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