The first requirement is a loading spoon, to which the artificer gives the name corne. The diameter of this is equal to the interior diameter of the case. It should contain so much of the composition as is necessary for filling the case to a height of one-half the exterior diameter of the rocket. (Pl. II, fig. 9.)
Three hollowed sticks are necessary for loading the smaller rockets and four for the larger rockets. The hollowed-out space should be such for the first stick as to receive the whole length of the piercer; for the second, to receive two-thirds the length of the piercer; for the third, one-third the length of the piercer. Care must be taken that the dimensions of the cavity should be such as not to force the case while it is being loaded. In order that these sticks may be easily withdrawn, they are made a little smaller than the loading stick. (Pl. II, figs. 4, 5, and 6.)
A shorter stick of the same diameter as the others used in loading, but with no cavity, is called the massif. This is employed for loading that portion of the composition which extends above the point of the piercer. This part of the charge also is called the massif, by reason of its entire solidity. (Pl. II, fig. 7.)
A mallet of hard wood is advisable, but basswood will serve. The diameter of the head should be two and three-quarter times that of the mold, and its length three and a third times the same diameter; the handle five diameters, excluding the part that enters within the head. (Pl. II, fig. 10.)
When the case has been trimmed and reduced to the length of the mold, the piercer is rubbed with soap in order that it may penetrate more readily through the aperture left after the choking. This opening should be somewhat smaller than the largest part of the piercer, so that when the piercer is thrust through, the orifice will be shaped to roundness.
The exterior space beyond the point of choking is filled with string to render support to the case, which might otherwise be so weakened by the blows of the mallet as to cause the subsequent bursting of the rocket in this place. It is to be noted that, in spite of this precaution, the like disaster may be occasioned if the composition is compressed too forcibly. (Pl. II, fig. 11.)
The case is now placed in position over the piercer, and covered by the mold. The first loading stick is thrust down in the case, and given a dozen blows of the mallet, to fit it firmly in position, and also to smooth the folds over the choke. If these were allowed to remain uneven, they might cause spaces into which the air would enter, and so bring about the bursting of the rocket. (Pl. II, fig. 4.)
When the first loading stick has been withdrawn, a spoonful of the composition is poured in. The loading stick is then introduced gently into the case. It is pressed firmly against the composition, and light taps of the mallet compress the charge sufficiently. When the rocket is of 18 lines, the number of strokes is 40.
The operations with the second loading stick and with the third are made in a similar manner. The only variation is that, at each change of stick, the number of mallet blows is reduced by 5. The strokes on the massif, or solid part of the charge, should number 20. The reason for this diminution is to be found in the increase in amount of the material, in proportion to the height as the measure of the piercer lessens. A smaller surface is thus presented for burning, and there is, therefore, less need of compression.
When the rocket exceeds 18 lines in diameter, the number of mallet blows is increased in proportion to the size, up to 50 for the first loading stick. Afterward, from this number, the blows are diminished regularly by 5 for each stage, down to 25 for the shortest stick.
A rocket should be loaded with from 12 to 15 separate charges. Of these, 9 or 10, or more, serve for covering the piercer, and the other 2 or 3 for the massif.
When the massif has reached the level of the mold, a wadding of torn paper is placed upon it, to which are given a dozen blows. The part of the case left empty above the massif is folded over upon the wadding to half the thickness of the stick, and 20 blows are given to make it hold its position. Two or three holes are driven through the folds by a stop-awl under the blows of the mallet. The stop prevents too great penetration. It suffices if the hole reach to the composition. Extension too far would weaken the massif, and cause it to communicate its fire too quickly to the load. These holes are, of course, designed for the purpose of communicating fire from the massif to the load.
The rocket is next taken from the piercer. The string that retains the choke is removed, and that part of the case which exceeds the doubled-over pasteboard is trimmed off.
Unless the rocket is to be used immediately, it is further necessary to paste a thickness of paper over each end, in order to protect it from the influence of the air or possible fire. This precaution taken, the rocket will remain in good condition for a long time, if the materials used in the composition were thoroughly dry, and if the storage place also is wholly free from humidity.