“ Various chemists had traced numerical sequences among the atomic weights of some of the elements and noted connexions between them and the properties of the different substances; but it was left to him to give a full expression to the generalization, and to treat it not merely as a system of classifying the elements according to certain observed facts, but as a “law of nature” which could be relied upon to predict new facts and to disclose errors in what were supposed to be old facts. ”

“ Mendeléeff wrote largely on chemical topics, his most widely known book probably being The Principles of Chemistry, which was written in 1868–1870, and has gone through many subsequent editions in various languages. For his work on the Periodic Law he was awarded in 1882, at the same time as L. Meyer, the Davy medal of the Royal Society, and in 1905 he received its Copley medal. He died at St Petersburg on the 2nd of February 1907. ”

“ MENDELÉEFF, DMITRI IVANOVICH (1834–1907) , Russian chemist, the youngest of a family of seventeen, was born at Tobolsk, Siberia, on the 7th of February (N.S.) 1834. After attending the gymnasium of his native place, he went to study natural science at St Petersburg, where he graduated in chemistry in 1856, subsequently becoming privatdozent. ”