The most effective apparatus yet invented is col. Boxer's. Finding that Dennett's parallel rockets On one stick do not work well, he succeeded after many trials in a mode of placing two rockets in one tube, one behind the other. The head is of hard wood; there is a wrought-iron case, with a partition between the two rockets. When fired, the foremost rocket carries the case and the attached line to its Maximum distance, and the rearmost rocket then gives these a further impetus. The effect is found to be greater than if the two rockets were placed side by side, and also greater than if the quantity of composition for tho two rockets were made up into one of larger size. The rocket is fired from a triangular stand, and is lighted by fuse, port-fire, or percussion-tube; tke ele vation is determined by a quadrant or some similar instrument.
The lines used with these several projectiles have varied greatly; but the best is found to be Italian hemp, spun loosely. It is very elastic, and when thick enough for the pur pose, 600 yards weigh 46 lbs. In Boxer's rocket, the line passes through the tail of the stick, then through the head, where it is tied in a knot, with India-rubber washers or buffers to lessen the jerk. The line is carefully wouud on a reel, or coiled in a tub, or faked in a box provided with pins ranged round the interior—to enable the line to run out quickly without kinking or entangling. Dennett's faking box for this purpose is the one now generally adopted.
Life-belts, jackets, and buoys of various kinds are used, made of cork, inflated India rubber, etc.; but one apparatus now employed in conjunction with the life-rockets is known by the curious name of or more simply, sling It is not strictly either a belt or a buoy, but a garznent in which a inan may be slung clear out of the water. When. a rocket has been fired, and a line has reached the distressed ship, signals are exchanged between the ship and the shore; a thicker rope is pulled over to the ship by means of the line, and a hawser by means of the rope. When all is stretched
taut, by fastening to the masts, etc., articles can be slung and drawn to and fro. T110 petticoat-breeches, invented by lieut. Kisbee. consists of a circular cork life-buoy form ing the top ring of a pair of canvas breeches; one of these is hauled over from the shore to the ship; a man gets into it, his legs protruding below the breeches, and his armpits resting on the buoy; and he is hauled ashore by block-tackle. The crew of a wrecked ship can thus one by one be relieved. To prevent losing the hawser and other apparatus, when the last man has left the ship, an apparatus called a hawser-cutter is used, working in the ship, but worked from the shore. Other apparatus will be found, noticed ha LIFE-PRESERVERS.
After the destruction of the Norajleet in 1873, off Dungeness, an exhibition was organized at the London tavern, to which the inventors of new life-saving appliances were invited to contribute. Among the apparatus were Hurst's consisting of a double pontoon, bridged over, stowed outside a ship, and lowered by simply cutting the lashings; Christie's a large rectangular framework, rendered buoyant by numer ous air-tight spaces, some of which are available for stowing water and provisions; and Parratt's tubular composed of cylindrical air-bags made of painted canvas, sup porting a flooring of sail-cloth and netting, and rendered rigid by poles fixed in various directions. Many other novelties were displayed at the London tavern, and also at a similar collection in the annual international exhibition, in the forms of life-boats, rafts, garments, belts, buoys, etc. Since then, nothing new and important has been introduced in connection with life mortars and rockets or their appendages.