The ball comprises a glass globe rather larger than a pea, having a small aperture, into which should be put from one third to half a grain of Brugnatelli's Fulminating Silver: a piece of paper is then to be pasted carefully all over the ball, in order to cover the glass and prevent the escape of the Silver.--The method of using the balls is to throw them down smartly, or to place one under the ball of the heel and tread hard upon it, which causes an explosion equal to a pistol and free from danger; the latter method of using them is generally preferred, and is assuredly the most certain. * * * * * A Bomb consists of the same materials as a ball, only on a larger scale: the globe for a bomb is the size of a common nut, and the quantity of Brugnatelli's Fulminating Silver is from one grain to one grain and a half, according to the report wished to be produced. The way of applying bombs is by throwing them down with violence, and it should here be remembered that this is the less exceptionable method of using them: they should on no occasion be used, without apprising the bye-standers, nor must they ever be pressed on by the foot; as the shock produced by the detonation would be rather too violent. FULMINATING SPIDERS. The Spider is formed after the manner of the common spider, it has a glass body, into which is put one third of a grain of fulminating silver. The manner of using: being formed in every respect so as to resemble the spider, they may be left on the ground, in closets, or on any article of wearing apparel, from whence they will consequently soon be dislodged, and from the natural antipathy towards this disagreeable insect, there can be no doubt of its being soon trod upon, when, to the no small surprise of the treader, a report equal to that of a pistol will be produced.--Many persons apply them to Ladies' Dresses, but from the well-known delicacy of female nerves, it were better perhaps to abstain from this experiment. Observe, the spiders cannot be exploded but by pressure, which is best done by the foot. FULMINATING CARDS & SEGARS. The Card is of the pattern herein enclosed; it must be opened at one end with a pen-knife, as here shewn, into which opening put one-fourth, or one-third of a grain at most, of Fulminating Silver; the edges are then to be pasted slightly, and closed together; a notch should also be cut at the other end, as in the pattern. When dry it will be complete for use. The manner of using, is to take it by the notched end, and light the square end at the candle, when a sharp detonation ensues.--The Card should be three quarters of an inch wide, and from four to five inches in length. Cards thus prepared, have long sold in Paris under the denomination of "Detonating Cards." * * * * *