Page:The fairy tales of science.djvu/94

 which we do know something, namely, the relative weights of the ultimate particles or atoms of bodies.

Chemistry has revealed the existence of some sixty-three elementary bodies, or, according to the atomic theory, sixty-three different kinds of atoms. Now, although we cannot ascertain the actual weight of a single atom, we have good grounds for believing that an atom of oxygen is heavier than an atom of carbon and lighter than one of sulphur. Before we enter into this subject, we have a few words about the great man who revived the ancient theory of atoms, and made use of it to explain the mysterious laws of chemical combination.

John Dalton was born in Westmoreland, in the latter portion of the last century, and belonged to the sect of Quakers. When very young he resided with Mr. Gough, of Kendal, a blind philosopher, to whom he read, and whom he assisted in his scientific investigations. It was here that he acquired a considerable part of his education, particularly his taste for mathematics. From Kendal, Dalton went to Manchester, and commenced teaching elementary mathematics to young men. In this way, together with a few courses of chemical lectures which he occasionally delivered, he contrived to support himself during a long and useful life. His slender income was always equal to his wants, and in his contempt for riches he resembled the sages of antiquity.

His kind heart and powerful mind gained him many friends and admirers, and in course of time