INTRODUCTION.

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We have thus, in this brief and hasty outline of the nature,principal effects, and properties of caloric, detailed the leadingfacts on this subject; from which it will be seen, that caloric, sofar as respects its generation by the combustion of different pyro-mixtures, and effects, generally, should form a part of Pyrotechny and claim the attention of those, who are connected with the pre-paration of Fire-Works .

Respiration is also a process which puts quiescent heat in mo-tion.*

In the second part of the work, we embrace the furniture of alaboratory, for the use of fire-workers, consisting of various toolsand utensils.

Under this head, we also embrace sundry manipulations, suchas the preparation of substances for use, the manner of formingmixtures, and various anterior operations. The formation of paste-board for cases, the mode of forming as well as charging cases,

with almost every obstacle. Livy tells us, that Hannibal softened the rockby pouring vinegar upon it, after it had first been made hot under flamingpiles of huge trees! M. Rollin quotes Pliny to prove that vinegar has theforce to break stones and rocks! This story is altogether fabulous; fo^in the first place, had fie vinegar sufficient; and, secondly, who ever knewthat vinegar had force, or even the power of dissolving primitive rocks,such as granite or gneiss; and, thirdly, if it possessed the power stated byPliny , and had he a sufficient quantity, where was his wood? For Polybiusassures us, that Hannibal had no wood to make a fire with, and that therewas not a tree in the place, where he then was, nor near it. That Hanni-bal passed over the Alps into Italy , and at an inclement season of the year,is certain, and that it was one of the greatest achievements that an enter-prising commander ever accomplished, is generally admitted.

* Respiration is a mechanical and chemical process, and consists in al-ternate inhalation and exhalation, which, in consequence of the oxygen gasin the air, effects a change in the venous blood that enters the lungs fromthe pulmonary artery. Now as this blood is charged with carbon, to whichits dark purple colour is owing, it is carried off in union with oxygen inthe form of carbonic acid. Hence carbonic acid is produced in respiration,and the venous blood is changed into the bright red arterial blood. Acommon sized man will consume about 46 thousand cubic inches of oxy-gen per diem; equivalent to 125 cubic feet of air, and makes about twentyrespirations in a minute, or for every seven pulsations breathes twice,e