With respect to the arrangement and display of sundry pieces of fire-works, either alone or combined, the effect depends, as well upon the ingredients, which compose the several sorts of fire, as on the taste displayed in their exhibition. It would be altogether unnecessary to notice, at this time, the order of exhibition usually adopted, reserving this subject until we have gone into the various preparations, which constitute, as it is called, a _system of fire-works_. In order, however, to become familiar with the manner of arranging them, as well as with their composition and preparation, whether designed for a general or a partial display, for the open air or for rooms, we purpose to appropriate distinct chapters for their consideration. The variety of preparations, which become necessary where a full exhibition is intended, the accuracy of the different mixtures, and the adjustment of cases to wheels, whether vertical or horizontal, and the arrangement of the leaders, or communicators of fire, from one part to another of the work, with many other circumstances, in relation to stars, rain, &c. all require, from the artist, particular care and attention. For the mere exhibition of one or two pieces, as a plain rocket, rocket with serpents, or the like, and likewise for some exhibitions, on water, called aquatic fire-works, in rooms or apartments, with scented fire, or on the stage; the preparations are by no means extensive. It is, therefore, our design to present a view of the whole subject in detail, and to speak of the different combinations of arrangement, which are made according to fancy and taste, and calculated, as we have remarked, either for small or extensive exhibitions. We have, in a preceding part of this work, made some observations on certain preliminary operations; on the various sizes and charges for cases; on the paper, necessary to be used, for different kinds of cases; and, generally, on sundry manipulations, connected with the making, filling, and preparation of sundry descriptions of fire-works. It remains, therefore, in the course of this subject, to give the several formulæ, with such observations as immediately concern the subject; and for this purpose we will pursue the following order: Frazier is of opinion, that the arrangement of fire-works, which have been exhibited with effect, may, on particular occasions, be established as a guide. For this reason, Morel introduces an account of the celebrated fire-works at Versailles and Paris, in 1739, which we shall here notice. _Exhibition of fire-works at the city house of Paris, on occasion of the peace in 1739._ The theatre was a building, forty feet square, with a pyramid of eighty feet in height, on which was placed a globe, containing artificial fire, and accompanied with sixteen large vases of different forms. All the edifice was ornamented with a variety of decorations, combined with figures and emblems of peace, and painted on marble.