When smaller cases, however, are to be made, such as for serpents, speckles, or fires on a little scale, it is much more convenient to use very long formers, so as to make up a great quantity of case at one time. When it is thus made, it can he cut off in lengths while upon the former, and then withdrawn. For making the cases of spiral wheels also, or the leaders for quick match, long formers are wanted ; and these are most conveniently made of copper wire. Care must be taken that they are kept very straight, without which pre caution it will be found very difficult to withdraw them.
\Ve shall now subjoin a table of the diameters for a set of formers, which will equally serve the purpose of one for that of rammers. It is necessary, however, that these should differ just so much that the rammer may slip easily up and down in the case, and that, after it is dry. On the different sizes, from the smallest up wards, these differences will vary a little; as they may be trifling in the smaller, and require to be somewhat more considerable in the larger ones. A correct turner will manage this without any prescribed measurement, which indeed could scarcely be given to any useful purpose, as it is in parts of an inch so very minute. But it may be considered as a sort of general rule, that if the rammer is so much smaller than the former as to require a turn of the cartridge paper to bring it to the same size, it will be able to move freely in the case in ramming.
These dimensions are such that they will also serve for the table of rockets which will hereafter be given, as it is unnecessary to multiply the sizes of cases. A '.mailer number, indeed, than even the preceding, may answer all useful purposes. When cases become large, and if they are only intended for discharging serpents and stars in the manner of mortars, formers are unne ccssary, as it will be cheaper to make thetn of wood, when they may be square, or to have them constructed in gun metal, like mortars or patereroes.
The lower end of all formers should be turned into a hemispherical shape ; and, besides that, a correspondent piece, similarly turned at one end, and much shorter, is required. The purpose of this is to introduce, during the operation of choaking, the cases; as the string is passed round an interval left between the former and its subsidiary piece, by which means it is kept in a proper shape, and prevented from collapsing. All formers, with their additional pieces, should be lettered so as to correspond each with its own rammer and mould similarly marked, by which chances of mis take are prevented.
Rammeis. Although the lengths of formers may exceed that of the cases to almost any extent, those of rammers must be limited to little more than the lengths of the different cases to be driven ; particularly in the larger, that are to be used with a mallet The smaller, if loaded, and only to be used by the hand, may be double the length of the cases to be driven : in the smallest of all they may even be much more. But in going upwards, the lengths must be reduced so as not to exceed that of the case by more than one or two diameters. It will be recollected, that as the filling of the case proceeds, the rammer is always becoming longer ; or, what is the same thing, is rising beyond it, so as sometimes indeed to render it necessary that it should be changed for a shorter one. This is particu larly the case in the larger pieces, and in rockets, as we shall shortly see.
There are two kinds of rammers, solid and hollow. The first are used for most of the fixed fires, and the last are required for rockets, and occasionally also for wheel-cases, or other moveable fires. \Ve shall de scribe the solid ones first, as the most simple. For the smaller, where the mallet is not required, it is abso lutely necessary that they should be made of gun metal, and provided with a head, for the purpose of adding to the weight. It is also good economy to use metal rammers, even with the mallet, as far upwards at least as half an inch or more in diameter. This, in the driving of fuses or portfires, is absolutely necessary, on account of the great force which is required. We need scarcely say that they must be made very true and smooth, and the sharpness at the lowest end, round the edge of the circle, must he rounded off to prevent them from catching the inner side of the case and forc ing down the paper.
For wooden rammers, beech and ash are the best woods, and these also must be made very smooth and true ; besides which, they must be kept dry in such a manner as to prevent any hazard of their becoming warped. At each end, above and below, they must be bound with a stout hoop or ferrule of gun metal, to prevent them from splitting at one end or burning at the other; and these must be fastened in with metallic pins, to prevent them from slipping off when the wood may chance to shrink.