The elements of experimental chemistry Author:William Henry 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: 14- CHAPTER II. OF CHEMICAL AFFINITY. ALL bodies, composing the material system of the universe, have a mutual tendency to approach each other, whatsoev... more »er may be the distances at which they are placed. The operation of this force extends to the remotest parts of the planetary system, and is one of the causes that preserve the regularity of their orbits. The smaller bodies, also, that are under our more immediate observation, are influenced by the same power, and fall to the Earth's surface, when not prevented by the interference of other forces. From these facts, the existence of a property has been inferred, which has been called attraction, or more specifically, the attraction of gravitation. Its nature is entirely unknown to us; but some of its laws have been investigated, and successfully applied to the explanation of phenomena. Of these, the most important are, that the force of gravity acts on bodies directly in proportion to the quantity of matter in each; and that it decreases in the reciprocal proportion of the squares of the distances. From viewing bodies in the aggregate, we may next proceed to contemplate them as composed of minute particles. Of the nature of these particles, we have no satisfactory evidence. It is probable that they consist of solids, which are incapable of mechanical division, but are still possessed of the dimensions of length, breadth, and thickness. In simple bodies, the particles must be all of the same nature, or homogeneous. In compound bodies, we are to understand, by the term, particles, the smallest parts into which bodies can be resolved without decomposition. The word atom has of late been revived, to denote both these kinds of particles; and we may, therefore, speak with propriety of simple atoms and of compound atoms. When tw...« less