Invention of an effective and unfailing method for forming an instantaneous communication with the shore in shipwreck, and illuminating the scene in the dark and tempestous night / [John Murray].

John Murray

Date:: 1831

Credit: Invention of an effective and unfailing method for forming an instantaneous communication with the shore in shipwreck, and illuminating the scene in the dark and tempestous night / [John Murray]. Source: Wellcome Collection.

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$nearly two pounds, and at an angle of about 45°, a stout line, the thickness of a macharel line, with 2 ounces of gunpowder, was carried 104 yards. 2\ ounces.do.110 do. 3 ounces.do.130 do. It was found essential to the success of these experiments that the arrow should be properly shielded at the but- end by a plate of copper, and shod at its narrow summit with iron: and if the parallel iron rod, traversed by the ring, be preserved in its proper position by a shoulder and nut on the opposite side, as is indicated accurately in the plate and in the superior figure, and the ring be pro¬ perly welded and made of sound tough iron, freely tra¬ versing the rod, the conditions of success are secured. It may be found advisable also to use a small portion of platted cord in immediate contact with the ring, or any other pliant and tough material, as a thong or strip of lea¬ ther about six or eight inches long. In the blunderbuss, however, we found this altogether unnecessary. To di¬ minish the effects of friction, the parallel rod may be rubbed with a little lard mixed with black lead; and a slip of cork towards the angle whither the ring glances, will, by its soft, pliant and elastic character, diminish the impetus of the ring by its necessary resilience. This ring should be formed of a faeiculus, or bundle of tough wires, twisted together and moulded finally at a proper tempera¬ ture into the required form. This method will amply secure the full amount of strength requisite. In subse¬ quent experiments, made on the cliff in the teeth of a strong gale of wind, the arrow, which weighed exactly one pound and a half, with a charge of only two$