A System of Pyrotechny. James Cutbush

the component parts of gunpowder, so as to determine their proportions? What are gunpowder proofs? What is understood by the comparative force of gunpowder? What are eprouvettes? &c. In noticing in the same manner the preparations used for fire-works, and for war, as the rocket for instance, the following questions were propounded; viz. What is a rocket? How is it formed? Is the case always made of paper? What is the war rocket? What is the composition for rockets, and how does it act? What particular care is required in charging a rocket? What is the cause of the ascension of rockets? What is the use of the conical cavity, made in a rocket at the time it is charged, or bored out after it is charged? How do cases charged with composition impart motion to wheels, and other pieces of fire-work? What is understood by the rocket principle? What is the rocket stick, and its use? Is the centre of gravity fixed, or is it shifting in the flight of rockets? How are rockets discharged? What is the head of a rocket? What is usually put in the head? Are all rockets furnished with a head? What is understood by the furniture of a rocket? How are the serpents, stars, fire-rain, &c. forming the furniture of a rocket, discharged into the air, when the rocket has terminated its flight, or arrived at its maximum of ascension? What forms the difference between a balloon, in fire-works, and a rocket? As the balloon contains also furniture, and is projected vertically from a mortar, how is fire communicated to it, so as to burst it in the air? Is the fuse used, in this case the same as that for bombs, howitzes, and grenades? What is the Asiatic rocket? The fougette of the French? In what seige were they employed with success by the native troops of India? What was the nature of their war-rocket? What is the murdering rocket of the French? Is the conical head hollow, or solid, blunt or pointed? Why is it called the murdering rocket? What is the Congreve rocket? Is Congreve the inventor, or improver of this rocket? What are Congreve rockets loaded or armed with? In what part is the load placed? Is the case made of paper or sheet iron? What are the sizes of Congreve rockets?

      What are the ranges of Congreve rockets? What angle of elevation produces the best range? How are Congreve rockets discharged in the field, and what number of men are usually employed for that service? Are the Congreve rockets considered to be a powerful offensive weapon; and, if so, in what particular? What is a carcass rocket? As an incendiary, is the carcass rocket equal to the usual carcass thrown from mortars? What is the carcass composition made of? What is the Congreve rocket light ball? In large rockets, are their sticks solid, or bored and filled with gunpowder? Why is that expedient used? &c.

      It is obvious, that the student, after obtaining a knowledge of each subject by the preceding lecture, accompanied with demonstrations, is enabled to detail minutely all the facts in relation to it.

      Pyrotechny, as known at present, is confined to a few books, and scattered in a desultory manner, without any regular or connected system. In fact the works which treat on this subject are in French, or translations from the French on particular subjects, but generally very imperfect. As applied to the uses of war, we may indeed say, that the small treatise of Bigot, (Traité d'Artifice de Guerre), and Ruggeri (Pyrotechnie Militaire) are the only works. We have, therefore, consulted these authors, as will be seen in the pages of the work.

      Roger Bacon, in his Opus Majus, has given some account of the Greek fire, and of a composition, which seems to have had the effect of our modern gunpowder.

      Malthus (Traité de l'Artillerie) contains some formulæ for Military Fire-Works. Anzelet and Vanorchis, in their several works, have given some receipts for incendiary preparations. Henzion (Recreations Mathématiques) and Joachim Butelius have also something on the subject.

      The celebrated Polander, Casimir Siemienowicz, has nothing of any moment, if we except the incendiary fire-rain, an account of which may be seen in the fourth part of our work. His book is considered, however, the best of the whole of them. Belidor, Theodore Duturbrie, &c. have mentioned some preparations; but their works are chiefly confined to artillery.

      The improvement of Pyrotechny is ascribed to the Germans and Italians, and the French acknowledge, that they are indebted for a knowledge of it to the Italians. Be this as it may, it is certain, that it was known in China from time immemorial. Their acquaintance with gunpowder, before it was known in Europe, is a fact which appears to be generally admitted. For an account of the Chinese fire-works, and the origin of gunpowder in Europe, consult these articles respectively.

      Whatever merit we may claim in this work, as the public will be able to judge impartially, it will be seen, by referring to the different chapters and sections, that we have endeavoured to form a system, by presenting a connected view of the whole subject.

      Having noticed under separate heads, the particular use and application of each composition, we have added a chapter on the arrangement of fire-works for exhibition, together with the order to be observed. We may remark here, that we have enlarged in this part more perhaps than its merit or importance deserves; but, on reflection, we thought it better to embrace the whole subject, in order to form a more complete system in all its parts.

      After going through the fire-works for exhibition, and noticing the different formulæ, and preparations, for arrangement, with the theory of effects, we consider, in the next place, a subject of more importance, that of Military Pyrotechny. We have adopted this arrangement, more on account of obtaining a better acquaintance with ordinary fire-works, before the reader is prepared for military works, which he will understand with more facility; for all the preliminary operations precede the practical part.

      On this head, it will be sufficient to add, to what we have already stated, that we have given in each article, generally speaking, a variety of formulæ, with ample instructions for the preparation of each composition. The table of contents will exhibit the order in which they are treated.

      In noticing the substances used in fire-works, in the first part, it will be perceived, that we have noticed some of them more extensively according to their importance; as for instance, saltpetre. Besides the different modes of obtaining saltpetre in Europe and elsewhere, and the means employed for refining it, we mention the saltpetre caves of the western country, which furnish an abundance of this article, and which contain an almost inexhaustible supply.

      The extraction of saltpetre from the earth, (principally nitrate of lime), by using a lixivium of wood-ashes; the formation of rough, and subsequently of refined nitre; the various methods of refining saltpetre, and particularly that adopted in France; with sundry facts respecting the origin of nitre, and on the formation of artificial nitre beds; all claim our particular notice.

      The extraction of sulphur from its combinations, and the means used for purifying it for the purpose of gunpowder, are also considered in the same manner.

      The subject of charcoal, an essential constituent of gunpowder, claims, in like manner, particular attention. The various modes of charring, the woods employed, the quantity of coal obtained, the formation of pyroacetic acid in the process of carbonization, and many facts of the same kind are considered. These subjects, viz. nitre, charcoal, and sulphur, are highly important to the manufacturer of gunpowder.

      A knowledge of the various processes for refining saltpetre; the best and most approved modes of carbonizing wood; the purification and quality of sulphur; the different processes for making gunpowder, with the proportion of the ingredients used in France and elsewhere; the granulation, glazing, and drying of powder, the use of the steam apparatus, and the different modes of proving it, and of examining it chemically; and the means of ascertaining the purity of nitre in any specimen of gunpowder; are, with others, subjects of particular interest to the gunpowder manufacturer.

      With respect to the Theory of the explosion of gunpowder, we have noticed it at some length, and have added the experiments and observations of Mr. Robins, and of other persons, made at different periods.

      In the consideration of the gaseous products, and the caloric evolved by the combustion of powder, we have taken a view of the gases produced, the cause of their production, the dilatation which they suffer, and the experiments of Lavoisier and Laplace, with regard to latent heat, and deducing therefrom some views of the probable cause of the production of caloric in fired gunpowder.[7]

      Our observations respecting rockets, the theory of their ascension, of the Congreve carcass and Asiatic