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.