Fig. 7.—Wasteneys Smith’s Stockless Anchor.
when “let go” does not hold so quickly as a stocked one, is more uncertain in its action over uneven ground, and is more liable to “come home” (drag). The stockless anchors principally in use in the British navy are Hall’s improved, Byer’s, and Wasteneys Smith’s. In Hall’s improved (fig. 5) the arms and crown of cast steel are in one piece, and the shank of forged steel passes up through an aperture in the crown to which it is secured by two cross bolts. Two trunnions or lugs are forged to the lower end of the shank.
In Byer’s plan (fig. 6) the flukes and crown consist of a steel-casting secured to a forged shank by a through bolt of mild steel, the axis of which is parallel to the points of the flukes; one end of the bolt has a head, but the other is screwed and fitted with a phosphor bronze nut to allow the bolt to be withdrawn for examination. A palm is cast on each side of the crown to trip the flukes when the anchor is on the ground, and for bringing them snug against the ship’s side when weighing. Wasteneys Smith’s anchor (fig. 7) is composed of three main parts, the shank and crown which form one forging, and the two flukes or arms which are separate castings. A bolt passes through the crown of the anchor, connecting the flukes to it; to prevent the flukes working off the connecting through bolt, two smaller bolts pass through the flukes at right angles to the through bolt and are recessed half their diameter into it.
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| Fig. 8.—Starboard Bow of H.M.S. “New Zealand.” |
Fig. 8 represents the starboard bow of H.M.S. “New Zealand” (16,350 tons) with lower and sheet (spare) anchors stowed. To let go a stockless anchor (fig. 9) the cable or capstan holder C is unscrewed, and in practice it is found desirable to knock off the bottle screw-slip A, allowing the weight of the anchor to be taken by the inner slip A′ (Blake’s stopper). Stern, stream and kedge anchors are usually stowed with special davits. A portable anchor suitable for small yachts is the invention of Mr Louis Moore; the shank passes through the crown of the anchor like the handle of a pickaxe and the stock over the head of the shank. At the end of the stock are loose pawls. There are no keys or bolts, and the only fastening is for the cable. The anchor takes to pieces readily and stows snugly. In 1890 Colonel Bucknill also invented a portable anchor for small yachts.
Iron buoy-sinkers (fig. 10), as used by the London Trinity House Corporation, weigh from 8 to 40 cwt.; the specified weight is cast on them in large raised figures, and the cast and wrought irons used are of special quality, of which samples are previously submitted to the engineer-in-chief.
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| Fig. 9.—Forecastle of H.M.S. “New Zealand.” | |||
| A. | Bottle or screw-slip. | B. | Deck or navel pipes. |
| A′. | Slip or Blake’s stopper. | F. | Fairleads for wire hawsers. |
| D. | Bitts. | H. | Hawse-pipes. |
| C. | Cable or Capstan-holders. | S. | Stopper-bolts. |
| C′. | Centre line capstan. | R. | Rollers. |
Fig. 10.—Iron Buoy-Sinker.
The anchors supplied to ships of the British navy are required to withstand a certain tensile strain, expressed in tons, proportionate to their weights in cwts. New anchors are supplied by contractors, but repairs are made in H.M. dockyards, a record of its repairs being stamped on each anchor.
In the Anchors and Cables Act 1899 a list is given of authorized testing-establishments, with their distinctive marks and charges, and testing-houses for foreign-owned vessels are enumerated in Table 22 of Lloyd’s Register of British and Foreign Shipping. Cast-steel anchors, in addition to the statutory tests, are subjected to percussive, hammering and bending tests, and are stamped “annealed steel.” (J. W. D.)
ANCHOVY (Engraulis encrasicholus), a fish of the herring family, easily distinguished by its deeply-cleft mouth, the angle of the gape being behind the eyes. The pointed snout extends beyond the lower jaw. The fish resembles a sprat in having a forked tail and a single dorsal fin, but the body is round and slender. The maximum length is 818 in. Anchovies are abundant in the Mediterranean, and are regularly caught on the coasts of Sicily, Italy, France and Spain. The range of the species also extends along the Atlantic coast of Europe to the south of Norway. In winter it is common off Devon and Cornwall, but has not hitherto been caught in such numbers as to be of commercial importance. Off the coast of Holland in summer it is more plentiful, entering the Zuider Zee in such numbers as to give rise to a regular and valuable fishery. It is also taken in the estuary of the Scheldt. There is reason to believe that the anchovies found at the western end of the English Channel in November and December are those which annually migrate from the Zuider Zee and Scheldt in autumn, returning thither in the following spring; they must be held to form an isolated stock, for none come up from the south in summer to occupy the English Channel, though the species is resident on the coast of Portugal. The explanation appears to be that the shallow and landlocked waters, of the Zuider Zee, as well as the sea on the Dutch coast, become raised to a higher temperature in summer than any part of the sea about the British coasts, and that therefore anchovies are able to spawn and maintain their numbers in these waters. Their reproduction and development were first described by a Dutch naturalist from observations made on the shores of the Zuider Zee. Spawning takes place in June and July, and the eggs, like those of the majority of marine fishes, are buoyant and transparent, but they are peculiar in having an elongated, sausage-like shape, instead of being globular. They resemble those of the sprat and pilchard in having a segmented yolk and there is no oil globule. The larva is hatched two or
