BLTC Press Titles


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Tao Te Ching

Lao Tzu, James Legge (trans.)


The Secret Doctrine, Volume I Cosmogenesis

H. P. Blavatsky


Theory of Colours

Johann Wolfgang von Goethe


The Adventures of Sherlock Holmes

A. Conan Doyle


An essay on shooting [based on La chasse au fusil by G.F. Magné de Marolles].

by Essay

Excerpt:

To form a barrel in the manner generally practised, the workmen begin by heating and hammering out a bar of iron into the form of a flat ruler, thinner at one end than another; the length, breadth, and thickness of it, being regulatedby the intended length, diameter, and weight of the barrel. This oblong plate of metal is then, by repeated heating and hammering, turned round a cylindrical rod of tempered iron, called a mandril, whose diameter is considerably less than the intended bore of the barrel. The edges of the plate are made to overlap each .other about half an inch, and are welded together by heating the tube in lengths of two or three inches at a time, and hammering it with very brisk but moderate strokes, upon an anvil which has a number of semicircular furrows in it, adapted to the various sizes of barrels. The heat required for welding, is the bright white heat which immediately pre* cedes fusion, and at which the particles of the metal unite and blend so intimately with each other, that, when properly managed, not a trace is left of their former separation : this degree of heat is known by a number of brilliant sparks flying off from the iron whilst in the fire. Every time the barrel is withdrawn from the forge, the workman strikes the end of it once or twice gently against the anvil, in a horizontal direction: this operation, which the English artists term jumping, and the French, ejloquer, serves to consolidate the particles of the metal B % more more perfectly, and to obliterate any appearance of a seam in the barrel. The mandrills then introduced into the bore or cavity, and the barrel being placed in one of the furrows or moulds of the anvil, is hammered Very briskly by two persons besides the forger, who all the time keeps turning the barrel round in the mould, so that every point of the heated portion may come equally under the action of the hammers.—These heatings and hammerings are repeated until the whole of the barrel has undergone the same operation, and all its parts are rendered as perfectly contiguous as if it had been bored out of a solid piece. The number of heats given to each portion of two or three inches, depends chiefly upon the quality of the iron, the purer kinds uniting and consolidating much more readily and perfectly than the

ordinary ordinary ones; the very best, however, require at least three welding heats.

Whilst the barrel is in the fire, the French workmen have a practice of giving from time to time, slight horizontal strokes with the hammer, to the end they hold in their left hand, so as to communicate to the heated part, a vibratory motion that serves to disengage from the pores of the metal, and throw off, such particles as are in a state of fusion, and therefore not easily convertible into malleable iron: it also separates such scales and impurities as form upon, or adhere to the surface. This operation, however, can scarcely be necessary with the first view, where the iron employed is of a proper degree of purity; as by the repeated heatings and hammerings it has, in that case, already undergone, these heterogeneous and impure particles cles are in a great measure removed, and very little left behind except the pure fibres, as it were, of the metal.

The imperfections to which a barrel is liable in the forging, are of three kinds, viz. the chink, the crack, and thtjiaw. The chink is a solution of continuity, running lengthwise in the barrel. The crack is a solution of continuity more irregular in its form than the chink, and running in a transverse direction, or across the barrel. The flaw differs from both: it is a small plate or scale, which adheres to the barrel, by a narrow base, from which it spreads out as the head of a nail docs from its shank, and when separated, leaves a pit or hollow in the metal.

With regard to the soundness of the barrel, the chink andsaw, are of much greater importance than the crack, as

the

the effort of the powder is exerted upon the circumference, and not upon the length of the barrel. In a sword, or bow, the very reverse of this takes place; for if a crack, though but of a flight depth, occurs in either, it will break at that place, when bent but a very little; because the effort is made upon the fibres disposed longitudinally; whereas if the #ault be a chink, or even a flight flaw, the sword or bow will not give way. The flaw is much more frequent than the chink, the latter scarcely ever occurring but in barrels forged as above, in which the fibres of the metal run longitudinally; and then only when the iron is of an inferior quality. When external scad superficial, they are all defects in point of neatness only; but when situated within the barrel, they are of material disadvantage, by afford


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