Book Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1857 edition. Excerpt: ...fully, as they are connected with a variety of experiments which I have made. The principal feature in this shell is the ferrule or iron ring, the purpose of which I will explain. In making experiments with shot more than two diameters in length, I found a difficulty in procuring with them an expansion sufficiently even to cause their axis to coincide with the axis of the bore of the gun, unless by adopting means unsuitable for practical purposes. The first of the accompanying diagrams represents the position of such a shot with an expanding ring upon the hinder end only, before the discharge; and the second represents the position which the same shot frequently assumes after the discharge. After many attempts, I at length succeeded in effecting the above object by means of the ferrule, B, which acts in the following manner. Upon the explosion of the powder, the lower ring, D, is caused to expand and fill the grooves, and at the same moment is driven, together with the iron ring, B, in a forward direction; the latter acting as a wedge upon the top ring, C, causes it to expand sufficiently to fill the bore, thereby occasioning a simultaneous expansion at two points. The first effect therefore of the explosion of the powder upon the shot is to force its axis to coincide with the axis of the bore; it then drives it out in a perfectly straight direction. The freedom of expansion allowed to the powder by the formation of the hind part of the shell permits the first action to be accomplished before the whole body of the shell is sensibly moved from its place. Figs. 10 and 11, Plate II., represent the shell as it lies in the bore, before and after the discharge. There is no difficulty attending the loading with this shell, and no wadding is...