162

THE VIBRATING

TRACT 35.

zontal position, introduce the ladle with the powder carefullyinto it, to the very bottom of the bore; as the ladle lies inthis state, let an assistant push the gun gently forward a lit-tle, to raise the muzzle higher than the breech, and while hesupports it in this position, turn the ladle of powder halfround, to let the powder drop all out in the bottom of thebore; after which, draw out the ladle, and introduce theother or flat end of it, with which press the powder lightlyall together in the bore, and then let the gun gently downagain into the horizontal position.

13. After the, gun has been thus charged with the pow-der, and before firing it, the index must be set exactly to thebeginning of the divisions on the arch. This is done, byfirst setting it near the mark with the hand, and afterwardsbringing it exactly to it, by means of a screw in the otherend of the index, above the stand of the machine at g, inthis manner: with one hand press the upper or screw-end ofthe index down upon the bar of the stand, and at the sametime with the other hand turn the screw backward or for-ward, and you will perceive the lower end of the index at f,by that means, move slowly backward or forward, till itcome exactly to the beginning of the divisions.

14. Before firing the powder, observe to have the socketof the index e, which fits upon the horizontal axis of the ma^chine, always pressed to it with a moderate degree of fric-tion ; so that it may not sensibly obstruct the vibratory re Tcoil of the gun, and yet that the index may keep any posi-tion you give it, without slipping from the arch or the axis,as the gun returns again from the first vibration.

15. After the piece has been charged with the powder,and the index set exactly to the beginning of the divisionson the arch, as before described, it is to be fired by means ofa thread of quick-match in the following manner: takeabout 3 or 4 inches of fine quick-match, and introduce oneend of it into the vent till it touch the powder in the bore,leaving the remainder to hang loose on the outside; thenset fire to this with the port-fire, plucking this quickly away,