719,905. Harpoons. WESTLEY, RICHARDS & CO., Ltd. Oct. 14, 1953 [Oct. 21, 1952; April 23, 1953], Nos. 26369/52 and 11175/53, Class 9(1) A harpoon for catching whales comprises a barbed head 15 secured in but electrically insulated from the forward end of a tubular steel shank 10 adapted to fit over the spigot of a spigot gun, a closure 11 at the forward end of the shank to take the thrust of the propelling gases, and means for attaching a cable directly to the barbed head and for electrically connecting an electric conductor within the cable to the barbed head. The rear end of the head is screwed' into a thimble 12 of insulating material which is screwed into the front end of the shank and has a radial flange 13 which abuts the end of the shank. The head is provided with a neck 25 adjacent its rear end of axial length greater than twice the diameter of the cable, two axially spaced transverse bores 26, 27 being formed in the neck. The cable is threaded through the rear bore 27 and taken round the neck and under itself and then threaded through the forward bore 26 and clamped therein by a rod 29 extending axially through the head into the forward bore. The electrical conductor is bared and doubled back over the outer surface of the part of the cable within the forward bore so that it makes electrical contact with the wall of the bore. Three barbs 18 having flanges on their inner edges over the greater part of their length are pivotally mounted in angularly spaced slots 17 in the head and are guarded by longitudinal ribs 21 projecting radially from the head in front of the barbs. When extended outwardly the barbs abut the rear edges of the ribs and surfaces 22 in the slots thus relieving their pivots of load. The shank is covered with a sheath 31 of insulating glass fibre and is provided at its rear end with pivoted flukes which normally are retained flat against the shank by a light cord but swing out into positions at right angles to the shank if the harpoon penetrates for its full length into a whale. In order to cause the cable to follow axially behind the harpoon in mid air the cable is also attached to the rear end of the shank by a light strop, and a link with a cutting edge surrounds the strop and is connected to one of the barbs so that when the barb moves outwardly after the head has penetrated a whale the strop is cut. The nose 16 of the harpoon is detachably screwed on to the head and has a concave end face 23 providing a circular cutting edge; a second cutting edge may be formed to the rear, of the end face. The first Provisional Specification describes three methods of attaching the cable to the head. In the first method the head is formed with a waist and a single transverse bore and the cable is taken round the waist in a timber hitch and its free end is clamped in the bore by a stem formed on the nose and adapted to screw into an axial bore in the head. In the second method the head is formed with a transverse opening of truncated wedge shape. The end of the cable is clamped by the stem of the nose and a bight of the cable is passed through the opening from the narrow end and a bobbin is inserted into the bight. In the third method the cable is passed through a stocking of braided steel wire and clamped in a transverse bore in the head by the stem of the nose. The wires at one end of the stocking are brought together to form two strands which are formed into eyes to engage over studs provided on the head. A pull on the cable causes the diameter of the stocking to contract so that the stocking grips the cable over a considerable length.