Note: Project Gutenberg also has an HTML version of this file which includes the original illustrations. See 51326-h.htm or 51326-h.zip: (http://www.gutenberg.org/files/51326/51326-h/51326-h.htm) or (http://www.gutenberg.org/files/51326/51326-h.zip) Images of the original pages are available through Internet Archive. See https://archive.org/details/cu31924012367441 Transcriber's note: Text enclosed by underscores is in italics (_italics_). A carat character is used to denote superscription. A single character following the carat is superscripted (example: 0·01717_t_^2). Multiple superscripted characters are enclosed by curly brackets (example: V_{_0_}(1-K_t_)^{-1}). The ligature oe has been transcribed as [oe]. The dagger sign has been transcribed as [+]. The infinity sign has been transcribed as [oo]. THE PRINCIPLES OF CHEMISTRY by D. MENDELÉEFF Translated from the Russian (Sixth Edition) by George Kamensky, A.R.S.M. of the Imperial Mint, St Petersburg: Member of the Russian Physico-Chemical Society Edited by T. A. Lawson, B.Sc. PH.D. Examiner in Coal-Tar Products to the City and Guilds of London Institute Fellow of the Institute of Chemistry In Two Volumes VOLUME I. Longmans, Green, and Co 39 Paternoster Row, London New York and Bombay 1897 All rights reserved PREFACE TO THE ENGLISH TRANSLATION The first English edition of this work was published in 1891, and that a second edition is now called for is, we think, a sufficient proof that the enthusiasm of the author for his science, and the philosophical method of his teaching, have been duly appreciated by English chemists. In the scientific work to which Professor Mendeléeff's life has been devoted, his continual endeavour has been to bring the scattered facts of chemistry within the domain of law, and accordingly in his teaching he endeavours to impress upon the student the _principles_ of the science, the generalisations, so far as they have been discovered, under which the facts naturally group themselves. Of those generalisations the periodic law is perhaps the most important that has been put forward since the establishment of the atomic theory. It is therefore interesting to note that Professor Mendeléeff was led to its discovery in preparing the first Russian edition of this book. It is natural, too, that the further application and development of that generalisation should be the principal feature of this, the latest edition.