266 THE POPULAR SCIENCE MONTHLY. 



our atoms form distinct portions of an invisible world, as planets, 

 satellites, and comets form distinct portions "of the astronomer's 

 universe ; our atoms may therefore be compared to the solar 

 system, or to the systems of double or single stars. . . . Now that 

 the indestructibility of the elements has been acknowledged, 

 chemical changes can not be otherwise explained than as changes 

 of motion, and the production by chemical reactions of galvanic 

 currents, of light, of heat, or of steam-power, demonstrate visibly 

 that the processes of chemical reaction are inevitably connected 

 with enormous though unseen displacements, originating in the 

 movements of atoms in molecules." 



When, in 1880, the St. Petersburg Academy of Sciences refused, 

 in the face of strongly signed recommendations, to elect Mende- 

 leef a member in its Chemical Section, other scientific societies 

 hastened to express their appreciation of him by making him an 

 honorary member. Among these were the University of Moscow ; 

 the Russian Chemical and Physical Society, which presented him 

 an address where it spoke of him as " a chemist who has no equal 

 among Russian chemists " ; the University of Kiev, the Society 

 of Hygiene, etc. From England he received the Davy medal of 

 the Royal Society in 1882, and the Faraday medal of the Chemical 

 Society in 1889. 



Prof. Mendeleef is the author of a treatise on Organic Chem- 

 istry which was a standard work in its time, and which, accord- 

 ing to Prof. Thorpe, exercised a great influence in spreading 

 abroad the conceptions which are associated with the develop- 

 ment of modern chemistry. In 1863 he published a cyclopaedia of 

 chemical technology — the first really important work of the kind 

 produced in Russia. He has frequently been commissioned to 

 report on the progress of chemical industry as illustrated at the 

 various international exhibitions. His investigations and reports 

 on petroleum have been an important factor in the developing 

 of the trade at Baku, and in removing the monopoly which for- 

 merly dominated the market there. 



We quote again, in concluding, from Prof. Thorpe : " No man 

 in Russia," he says, " has exercised a greater or more lasting in- 

 fluence on the development of physical science than Mendeleef. 

 His mode of work and of thought is so absolutely his own, the 

 manner of his teaching and lecturing is so entirely original, and 

 the success of the great generalization with which his name and 

 fame are bound up is so strikingly complete, that to the outer 

 world of Europe and America he has become to Russia what 

 Berzelius was to Sweden, or Liebig to Germany, or Dumas to 

 France." 



