Patent GB-190214188-A (GB)
Title: Improvements in Marine Rocket-torches.
Inventor: UNDERWOOD WALTER JOHN
Filed: 1902-06-23
Granted: 1903-05-28
Abstract: 14,188. Underwood, W. J. June 23. Signals, marine. - Relates to a modified form of the combined marine torch and rocket described in Specification No. 13,355, A.D. 1901. The outer casing 1, Fig. 1, is of iron or mild steel and has a head 2 fixed in position after the torch is filled, and provided with the burners and sparkers for the torch. The lower part 3 is tapered, and a parallel part at the bottom receives the base plug 4,as described in the above-mentioned Specification. The rocket composition 5, consisting of ground saltpetre, sulphur, and alderwood charcoal, is insetted through the upper end, an air space 6 being left to facilitate the generation of gas for starting the rocket, and a space at the upper end receives calcium carbide to generate acetylene gas for use when the rocket floats on the water as a torch. A ball 7, having a metal core and a vulcanized rubber or other elastic covering, is placed in the upper part of the rocket composition, a perforated plate 10 covers the calcium carbide, and a cup-shaped plate 9 is placed below the calcium carbide to support it. In use, the rocket is fired from a trough in the ordinary manner, the composition burns away until the flame passes the ball and ignites the composition above it ; the gases generated then force the ball into the tapered part of the tube, in which it jams, and forms a water-tight plug. The calcium carbide, contained in an ordinary gauze casing, sinks to the bottom of the tube, water is admitted to it through the holes 11 and through grooves formed in the inner side of the tapered part of the tube, and the acetylene gas generated is ignited by sparks given off by calcium phosphide through the openings 13. When a parallel tube is used, a hollow water-check 14, Fig. 3. is provided, having the lower part cut away. The metal core has corrugations radiating from a point at the top to facilitate expansion when the ball is compressed, and the metal is coated with vulcanized rubber or similar material. The top plate 10, calcium-carbide charge 8, plate 16, and the water-check 14 are connected together by a small tube 17 filled with gunpowder or other explosive mixture and secured by nuts 18,19, or the tube may extend into the water-check, or into the rocket composition below the tube, the nut 19 being omitted. The head 2 is filled with rocket composition or other slow explosive, an air space 21 being left above the tube 17. In operation, the gunpowder in the tube ignites the composition 20, the gases generated force the charge 8 and watercheck downwards, and the sides of the check are expanded to form a water-tight plug for the tube. According to the Provisional Specification, the ball shown in Fig. 1 may be forced downwards by means of a small pellet of gunpowder placed above it and protected by varnished paper. Longitudinal grooves are formed in the tube around the ball, and are filled with gunpowder to carry the flame from the rocket composition to the pellet. The gunpowder in the grooves is protected by varnished paper or otherwise from damp. The ball may be replaced by a disc with a central opening, in rockets having a central torch chamber and a concentric chamber for the rocket composition. Specification No. 10,797, A.D. 1901, is referred to.