Submarine Appliances And Their Uses
Deep Sea Diving, &c., &c.

ROCK GRAPNELS (Photos F and G). t or working over rocky bottoms, where the prongs are likely to catch projecting rocks and get broken, Mr. Claude Johnson devised a grapnel in which the prongs are held in their working position by strong springs, the points of the prongs projecting slightly beyond the edge of a conical shield and arranged in such manner that, should a point hook on to a rock, the body of the grapnel with its shield ^automatically carried towards the rock and so releases the prong, which practically recedes under the shield. The weight of the Grapnel is 3} cwt. 7 Copyright. F. Copyright. G . _ Another form of Rock Grapnel frequently used is the Dutton Grapnel, or “ Umbrella ” Grapnel as it is sometimes called. This has five fixed prongs, which are protected (except for a small projecting portion at the points) by a conical corrugated shield, light flat springs being arranged to cover the opening between the shield and the point of the prong, so that after a cable is hooked there is no fear of it getting away. Weight 3 cwt. MURPHY PATENT GRAPNELS (Photo H). Ä A complete Grapnel consists of about four VJ sections, shackled together. Each section has five prongs, which are protected by wings in the same plane, so as to make it trail easily over ■■ rocky bottoms. The sections being short, the Grapnel is very I B flexible, and consequently searches well over W rocky ground, and the wings are a great pro- W tection against the prongs getting broken. à II | These Grapnels are made in four sizes, the sections weighing 20, 45, 58 and 85 lbs. each respectively. w' Copyright. RENNIE'S PATENT G R A P N E L ( F Copyright. This Grapnel consists of four or five, sections linked together. Each section is in the form of a large link similar to the links of a chain. Each link is provided with two prongs, and when fitted together the edges of the links protect the succeeding prongs. The links being short, the grapnel is very flexible, and being made of mild steel the grapnel is practically unbreakable, but the prongs are arranged so that they may be easily replaced should it be necessary. These Grapnels are made in several sizes, weighing from 12Å lbs. to 4^0 lbs per set. ‘ ° MUD GRAPNELS (Photo J). For working in muddy or sandy bottoms, Grapnels with long prongs are necessary to reach deep into the mud without the shank becoming embedded The common practice is to use a grapnel similar to the ordinary Grapnel but with longer prongs. Mr. Claude Johnson, however, has patented a Mud Grapnel which is constructed of steel plates, the web being a diamond-shaped plate arranged to glide over the surface of the mud while the prongs, which are at right angles to the web, search down into the mud. Weight 4 cwt." Copyright. 119