SKETCH OF DIMITRI IVANOVIGH MENDELEEF. 261 



SKETCH OF DIMITRI IVANOVIGH MENDELEEF. 



THE discovery of the periodic law in the atomic weights of 

 the elements has furnished chemists with a new standard of 

 accuracy and a new guide in research. While it must be regarded 

 as Mendeleef 's most conspicuous scientific achievement, the Rus- 

 sian chemist is the author of many othei labors of hardly less real 

 importance. 



DiMiTRi IvANOViCH Mendeleef was born at Tobolsk, Siberia, 

 February 7, 1834, the seventeenth and youngest child of Ivan 

 Paulovich Mendeleef, director of the gymnasium there. Soon 

 after his birth the father became blind and had to resign his 

 position, leaving the care of the family upon the mother, a com- 

 petent and energetic woman. She established and managed a 

 glass-works, and brought up and educated her family upon its 

 profits. Dimitri was sent to the gymnasium at Tobolsk, and, at 

 sixteen years of age, to St. Petersburg, where he was to study 

 chemistry in the university, under Zinin ; but was transferred to 

 the Pedagogical Institute in the same building with the univer- 

 sity, where he entered the physico-mathematical department, or 

 that of the natural sciences. He studied chemistry, physics, 

 mathematics, botany, zoology, mineralogy, and astronomy, under 

 teachers who were most of them also professors in the university. 

 Having concluded his course here, he was appointed to the gym- 

 nasium at Simferopol, in the Crimea ; then, during the Crimean 

 War, to a gymnasium in Odessa ; and in 1856 he became a Privat 

 Docent in the University of St. Petersburg, where he had already 

 received the degree of Master of Chemistry. In 1859, having ob- 

 tained permission from the Government to travel, he became 

 engaged at Heidelberg in the determination of the physical con- 

 stants of chemical compounds. In 18G3 he was made Professor 

 of Chemistry at the Technological Institute of St. Petersburg, 

 and in 1836 at the university, where he received the degree of 

 Doctor of Chemistry. 



Mendeleef had already^ before his engagement as a Privat 

 Docent^ entered upon the career of research and publication in 

 which he has so brilliantly distinguished himself. His first 

 paper, on Isomorphism, was prepared while he was still in the 

 Pedagogical Institute. He entered into the discussion of the 

 relations between the specific gravities of substances and their 

 molecular weights, and presented to the physico-mathematical 

 faculty of the university a number of theses or problems relating 

 to specific volumes ; and as early as 1856 he accepted Gerhardt's 

 mode of determining the chemical molecule. His researches on 

 specific volumes were continued till 1870, and in them, according 



