116 NICHOLLS'S SEAMANSHIP AND NAUTICAL KNOWLEDGE Crown Fig. §. /The anchor stock must be equal to one-fourth the specified weight of the anchor. It will be noted that this brings the weight of the anchor with stock up to approximately the same as the stockless anchor. The stock is to help the anchor to bite and get a good hold of the ground. Should the anchor fall with its arms flat, the stock will be upright, and as soon as any weight comes on the cable, the stock being heavy and longer than the arms, it will turn the anchor. This is the best holding type of anchor and the longer the shank the better it holds; it is, however, awkward to handle and stow on the forecastle-head. Stockless Anchors.—Figure 3 shows a Lenox unchokeable stock- less anchor; this type of patent anchor is now universally adopted in modern steamships. It consists of a heavy head having arms and flukes generally forged in one piece with it, also a shank and shackle. The head is made to turn on an axis perpendicular to the shank, the arms moving in a plane parallel to the shank, being in line with it when in the closed position. It is so constructed that the head will turn on its axis and the arms will open out to an angle of 45° with the shank, but no further. The head must weigh not less than three-fifths of the total weight of the anchor.