The Skylight and the Dark-Room: A Complete Text-Book on Portrait Photography; Containing the Outlines of Hydrostatics, Pneumatics, Acoustics, Heat, Optics, Chemistry, and a Full and Comprehensive System of the Art Photographic (Classic Reprint)

Excerpt from The Skylight and the Dark-Room: A Complete Text-Book on Portrait Photography; Containing the Outlines of Hydrostatics, Pneumatics, Acoustics, Heat, Optics, Chemistry, and a Full and Comprehensive System of the Art Photographic

The progress of Chemistry has pointed out a series of facts, which have led universally to a belief in the existence of very small particles of matter, by the union of which all masses of matter are formed.

Concerning any substance, the chemist asks: Of what is it composed? He endeavors to analyze it [11 e., to take it to pieces], and having found out of what it is composed, he seeks to put the parts together again to form the original compound. If he succeed in decomposing a substance, such substance is re. Garded as a compound Of simple substances; but if the substance cannot be decomposed by any known method of analysis, he regards the substance as being already at its simplest. Such simple substances, then, are called elements; all other are called compounds.

It has been agreed to call the smallest conceivable quantity of an element by the name of atom [z'. E. Uncut]. It has further been agreed to call the smallest conceivable quantity of a compound by the name of molecule. A molecule then always contains two or more atoms.

These atoms or particles are not considered as susceptible of any change, however varied the appearance of a mass of matter may be, owing to the manner in which they are grouped together. They may constitute a thin, invisible gas, a liquid, or a ponderous solid. Neither can they in any way be destroyed by any power that man possesses. They may appear and disappear to the eye, but they still exist. They may be hard, impenetrable particles, of such size and shape best suited to carry out the end for which they were created. They may never wear away, break, nor be divided.

All the researches and investigations of science, teach us that it is impossible for us to create or destroy a single atom; this power rests with the Deity alone.

About the Publisher

Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com

This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.