Fig. 24. This is a very splendid disposition of fire, which may be varied in different ways, as re presented in the same figure. It is in the first place a pyramid of wheels, with intermediate cases. Care must be taken to place them so that they may throw fires clear of the circles performed by the wheels. The arms may be illuminated or not, and there may also oe stars at the intersections. This machine may be treated on the principle of mutation. Thus tne lights may first be fired, afterwards the wheels, and last of all the fixed cases.
Fig. 25. This also is a very splendid firework, but it requires to be made on a very large scale. It may also be a piece of mutation, as the fixed cases may fire when the wheels are partly expended. The wheels should diminish gradually in diameter in ascending, while at the same time they have the same duration. • This is very easily managed, by placing the cases in somewhat of a spiral manner. Thus if a hexagon form be used at the bottom, the next may be a pentagon, with a case overlapping, and so on to the top; and as the same kinds of cases will be used in all, they will burn together. Wheels arc easily timed without this, in many ways in which we need not now point out, as all the general principles must by this time be well understood.
Fig. 26. The nature of this is too obvious to require explanation. It might easily become confused if care was not taken to keep all the parts well asunder. It is rather too formal for beauty, unless it were to form a part of some other larger design.
Fig. 27. This may be made extremely brilliant, but it requires a great deal of room. In constructing it, care must be taken that all the cases should be placed at the various angles indicated in the drawing, that a proper distribution of the brilliant fire may take place. The branches may be illuminated or not, as represented in different parts of the drawing. If il luminated, it should be made a mutation piece, by not bringing the brilliant cases into action till the wheel is partly expended.
Fig 28. This is a piece to be found in the com mon books, and it is one of the very 'few good ones which they contain It explains itself sufficiently,; and it will also be seen that it admits of modification, by the introduction or omission of the lights and stars But the best form of it is to fire the lights first, the wheel afterwards, and last of all the diverging cases at the ex tremity, which may be made of the same length and quality as the last case of the wheel, so that they may commence and terminate wick it.
Fig. 29. This is a very harAsome form of star, in any of the two or three shapes that arc represented on the same figure. Care must be taken that thv wheel do not throw its fires beyond the centre, so as to confuse illumination. It should also be managed on the ple of mutation, that the fires at the extremities may no burn till the last case of the wheel.
Fig. 30. This is a very handsome, but a complicated firework ; nor can it be moved without machinery. It is true that the books direct wheels to be placed at the feet of the cases, but the consequence of this is to pro duce confusion, and spoil the effect. The cones are made to revolve on spindles, in the same direction, so as to produce the appearance of a spiral motion. In the figure, a star is represented in the centre, with brilliant fires in the intervals of the cones ; but these parts may be varied in many different ways, as by the substitution of a wheel in the centre. The machine that is required for moving this firework is simple enough, as it is only a coutrate oblique wheel, moved by a winch or a weight, and acting on the endless screws which carry the cones, and form their axes.
Fig. 3I. This is a piece of architecture of a Gothic design; and we shall here remark, generally, that the Gothic, Chinese, and Oriental, or Arabic and Indian styles, are best adapted to fireworks, on account of the scope they allow to the fancy. Greek architecture is generally heavy and dull in fireworks ; while the artist is at the same time tied down to rules which are diffi cult to follow in this manner, and which ought not to be neglected. We have here represented only one of many ways in which the fires on such a figure as this may be varied ; and here also it is recommended that the cases of brilliant fire which represent the crockets should not be lighted till the last Plate CCCCLXXV. Fig. 27. This is a design on a very small scale, in a sort of oriental style. It will be sufficient if the dome is represented only in front, or that the hinder part be omitted ; but it may also be done with very little difference as to the effect, on a plane. The columns, which are twisted, may, if the artist thinks fit, be moved by machinery so as to represent each a moving spiral. Large lights may be used on the ends of the capitals, with or without a star in the middle. The front admits of many modifications, though we have given only a wheel with four stars.