Elements of chemistry - 1830 Author:Edward Turner Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: ELEMENTS CHEMISTRY. PART I. SECTION I. CALORIC. THE term Heat, in common language, has two meanings : in the one case, it implies the sensation ex... more »perienced on touching a hot body ; in the other, it expresses the cause of that sensation. To avoid any ambiguity that may arise from the use of the same expression in two such different senses, it has been proposed to employ the word Caloric to signify exclusively the principle or cause of the feeling ol heat, and the use of this term has now become so general, that I have adopted it in the present treatise. Caloric, on the supposition of its being material, is a subtile fluid, the particles of which repel one another, and are attracted by all other substances. It is imponderable ; that is, it is so exceedingly light that a body undergoes no appreciable change of weight, either by the addition or abstraction of caloric. It is present in all bodies, and cannot be wholly separated from them For if we take any substance whatever, at any temperature, however low, and transfer it into an atmosphere, whose temperature is still lower, a thermometer will indicate that caloric is escaping from it. That its particles repel one another, is proved by observing that it flies off from a heated body ; and that it is attracted by other substances, is equally manifest from the tendency it has to penetrate their particles, and be retained by them. Caloric may be transferred from one body to another. Thus, if a cup of mercury at 60 be plunged into hot water, caloric passes rapidly from one into the other, until the temperature in both is the same ; that is, till a thermometer placed in each stands at the same height. All bodies on the earth are constantly tending to attain an equality, or what is technically called an equilibrium of temp...« less