MARITIME CONVEYANCE. 



decks. Small open vessels, not possessing decks, 

 belong to the class of boats, of which there are 

 many varieties. They are divided into two lead- 

 ing classes, according to their mode of construe- | 

 tion. When made flush on the outside, and in ' 

 other respects like a miniature ship, they are 

 called carvel-built; and to this class belong long- 

 boats, pinnaces, yawls, c. When made with the 



Fig. 6. 



lower edge of each plank overlapping the upper 

 edge of the plank below it, they are called clinker- 

 built ; and to this class belong gigs, jolly-boats, 

 dingies. Diagonal-built boats have a double skin, 

 flush on the outside. Clinker-built boats possess 

 the greatest strength in proportion to their weight, 

 and are therefore most generally in use. The Mer- 

 chant Shipping Act regulates the minimum amount 

 of boat accommodation which passenger-ships are 

 compelled to carry, &c. The special class of 

 life-boats will be found treated of at the end of 

 this number. 



Ships always carry from four to six or seven 

 anchors. In large vessels, two dower-anchors, for 

 ordinary use, are kept on deck, while two exactly 

 similar are carried in case of accident ; a stream- 

 anchor is used for riding in sheltered places ; and 

 a kedge for warping the ship along a river's 

 channel. According to the report made by a 

 committee of investigation in 1852, the two an- 

 chors which were the best in every respect were 

 Rodger's and Trotman's. Of these, the former 

 was forged in one piece (excepting the cross-bar 

 or stock}) while the latter (shewn in fig. 7) has the 



Fig. 7. Trotman's Patent Anchor. 



arms separate from the shank. Loose arms have 

 several advantages, among which are that the 

 fluke which is not acting is not liable, from its 

 position, to foul the cable ; that the difficulty of 

 obtaining a sound forging at the junction of the 

 arms and shank is obviated ; and that the strain 

 is more advantageously distributed. The use of 



the stock or cross-piece, which is more often made 

 of iron than of wood as in the engraving, and 

 which always lies in a plane at right angles to that 

 of the arms, is to make the anchor cant on reach- 

 ing the ground, so that one or other of the arms is 

 sure to take hold. 



In every class of merchant-vessels the prime 

 object is to carry as large a quantity of goods as 

 possible, and therefore comparatively little space 

 is set apart for the accommodation of the captain 

 or his crew. If the cargo be light, or if the vessel 

 be returning empty from her port of delivery, 

 ballast is put in her hold, in order to give her the 

 immersion necessary for proper stability. Recent 

 researches have shewn how closely connected the 

 motions of a ship are with her degree of immersion 

 in the water as well as with her external form, and 

 it is now possible to calculate, with a near approxi- 

 mation to accuracy, the maximum angle to which 

 any ship, under given conditions of draught, &c. 

 will lie over, or heel, without tendency to upset 

 If her weights are wrongly placed, if she is, for 

 instance, top-heavy, owing to improper deck-load, 

 the naval architect can tell beforehand that if, in 

 rough weather, her heeling-over reaches a certain 

 angle, she will turn over, and go to the bottom. 

 In the navy, iron is used for ballast \ in merchant- 

 vessels, often sand, shingle, or any other heavy and 

 inexpensive material. No one who has ever sailed 

 up the Tyne to Newcastle can fail to have been 

 struck by the huge mounds of earth which line its 

 banks, and which often reach a height greater 

 than that of a ship's mast. The immense export 

 trade in coal from the Tyne so greatly exceeds its 

 imports, that the colliers in general return without 

 cargo, and therefore ' in ballast ;' and these 

 mounds are simply heaps of ballast taken out of 

 the ships, and placed, with much labour and cost, 

 in their present position. A much simpler plan 

 is, however, now adopted by all the colliers : 

 tanks are formed along the bottom of the ship ; 

 these are filled, when the cargo has been dis- 

 charged, with water ; and this water forms the 

 ballast. This plan has many advantages. The 

 water can be let in without any trouble, and can 

 be pumped out with very little trouble, and at the 

 same time as the vessel is being loaded ; while 

 ordinary ballast has to be hoisted in and out ; and 

 as it occupies the same space as the cargo, those 

 operations cannot be carried on at the same time 

 as the unloading or loading of the vessel. The 

 water-ballast also, being confined in tanks, is not 

 liable to shift with the motion of the ship as other 

 ballast may, and so prove a source of danger. It 

 has the disadvantage that the tanks permanently 

 lessen the cargo-space (although even this is not 

 always the case), but this is far more than counter- 

 balanced by the other considerations. 



LLOYD'S, &c. 



In order that a ship may be insured by the 

 underwriters, it has to be inspected and surveyed 

 by one of Lloyd's surveyors. According to the 

 reports of their surveyors the committee of Lloyd's 

 registry classify the vessel, affixing to its name a 

 letter, which is intended to be as nearly as pos- 

 sible a correct indication of its real and intrinsic 

 qualities. For wooden vessels, these letters (in 

 the order of excellence) are A (in black or red), 

 y, E, and I ; for iron ships or steamers, they arc 



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