372 NA LORE 
[ FEBRUARY 14, 1907 
to chemical science 
Menschutkin, 
To Beilstein’s life and services 
we have already made reference; of 
whose death has only just been announced, we hope 
to speak later. Our immediate concern is with the 
most distinguished of the eminent  triumvirate— 
Dmitri Ivanovitsch Mendeléeff. The chief facts of 
Mendeléeff’s personal history have been given in 
No. xxvi. of the series of “ Scientific W orthies,” which 
appeared in these columns so far back as 1889. It 
is sufficient here to recall that he was a Siberian, 
born at Tobolsk on February 7th (N.S.), 1834. He 
died, therefore, within a week of his seventy-third 
birthday. He was the seventeenth and youngest child 
of Ivan Paolowitsh Mendeléeff, Director of the Gym- 
nasium at Tobolsk, who, shortly after the birth of 
his son Dmitri, became blind and lost his position. 
The family thereby became practically dependent upon 
the mother, Maria Dmitrievna Mendeleeva, a woman 
of great energy and force of character, who estab- 
lished a glass works in the town, on the profits of 
which she brought up and educated her large family. 
The story of Mendeléeff’s youth and early struggles 
is given in the preface to his great work ‘‘ On Solu- 
tions,” which he dedicated to his mother’s memory 
in a passage of singular beauty and power. At the 
age of sixteen he was sent to St. Petersburg, but, 
owing to official restrictions, he was prevented trom 
studying chemistry under Zinin at the University, as 
he had intended, and was transferred to the Pedago- 
gical Institute, where he came under the influence of 
Woskresenky in chemistry, and of Lenz in physics. 
Whilst at the institute he wrote his first paper on 
“ Tsomorphism,’’ and after serving in the Gymnasium 
at Simferopol and at Odessa, he gained his Magister 
Chemiae in 1856, and was made a privat-docent in 
the University of St. Petersburg. 
At about this period he was attracted to the special 
line of inquiry and of speculation which was the 
dominant and most striking feature of his scientific 
activity, and which ey entually culminated in the great 
generalisation with which his name is inseparably 
connected. It is easy to detect in these early attempts 
at tracing the relations between the physical and 
chemical properties of substances and their molecular 
and atomic weights the germs of the conception 
which eventually took shape as the Periodic Law. His 
work on specific volumes was begun in 1855, and was 
continued by him in Heidelberg, where he went in 
1859, and where he remained until 1861. Germany 
would appear to have exercised no permanent influ- 
ence on Mendeléeff. He worked alone, and seems 
to have derived nothing from personal contact with 
Bunsen and Kopp. It is significant of his perspi- 
cacity that he should at this time have clearly appre- 
ciated and publicly declared his belief in the value of 
Gerhardt’s work on the determination of the chemical 
molecule—at the very period, in fact, when the whole 
weight of German authority was directed against the 
doctrine of the new French school. Returning to St. 
Petersburg, he became professor of chemistry. at the 
Technological Institute. In 1866 he was transferred 
to the University, and in 1890 he was appointed head 
of the Standards Department. 
Mendeléeff signalised his connection with the 
University by the publication of his ‘‘ Principles of 
Chemistry,” which has passed through many editions 
in Russia, and has been translated into German and 
English. It is not easy to avoid speaking of this 
work in terms which savour of hyperbole. Most 
treatises on chemistry owe a great deal to their 
predecessors. Indeed, there is probably no form of 
literature which so obviously proceeds on_ strictly 
evolutionary principles. But Mendeléeff’s great work 
is a thing apart—something sui generis. The bare 
facts of chemistry, in greater or legs detail, are com- 
NO. 1946, VOL. 75 | 
s, but most of them, we fear, 
Lamb among the books which 
It is not so with Mendeléeff’s “ Prin- 
ciples.” In its insight, in its grasp of detail and of 
principle, in its extraordinary power of coordination, 
in its suggestiveness, and in its wealth of speculation, 
it is a book among books, and may be read with profit 
and a pleasure occasionally tinctured with amusement 
by every true student, no matter how old. To those 
who had the good fortune to know its author person- 
ally it reflects the man in every page. Even the 
footnotes are instiact with character and originality. 
Mendeléeff’s “ Principles” may be ‘said to stand in 
the same relation to the chemistry of the latter haif 
of the nineteenth century that Dalton’s “New System” 
did to the chemistry of the earlier half. Each worl 
was the definite and orderly presentation of the doc- 
trine and philosophy of its author. 
There is hardly a department of chemistry in which 
Mendeléeff did not labour, at one time or other, dur- 
ing the thirty years of his activity as a teacher. 
Chemical mineralogy, chemical geology, and the 
chemistry of aliphatic substances in turn, and appar- 
ently with equal zeal, attracted his attention. It is 
to this catholicity and power of taking broad and 
comprehensive views of the operations ‘of chemistry 
that Mendeléeff owes his eminence as a chemical 
philosopher. But it is in the domain of physical 
chemistry that his fame as a worker chiefly rests. His 
early papers on the thermal expansions of liquids 
above their boiling points up to temperatures at which 
their cohesion and latent heats are nil, and at which 
the liquid becomes gaseous independently of pressure 
and volume, anticipated the researches of Andrews, 
and were, in their turn, a development of the obsery- 
ations of Cagniard de la Tour, Wolff and Drion. 
The same faculty of perceiving the underlying basis 
of a physical generalisation is seen in the notable 
paper which he communicated to our Chemical Society 
in the year following his election into that body as an 
honorary foreign member, in which he developed a 
general expression for the expansion of liquids under 
constant pressure, analogous to that which expresses 
Dalton’s law of the uniformity of expansion of gases. 
The formula V=1+kt applies only to a so-called ideal 
gas; in like manner, Mendeléeff’s expression is to be 
regarded only as a first approximation—that is, as 
applicable only to ideal liquids. In the case of actual 
liquids the deviations from the ideal form increase not 
only as the liquid approaches the point of change of 
state of aggregation, but also augment with diminish- 
ing density, increasing cohesion, and diminishing 
molecular weight, just as Mendeléeff himself showed 
that the deviations from Dalton’s law were related to 
the molecular weights of the gases. Subsequent 
observers, by applying van der Waals’s theory of the 
relation between pressure, volume, and temperature, 
have shown that the development of Mendeléeff’s for- 
mula affords a simple and ready method of calculat- 
ing the critical temperature of bodies from _ their 
thermal expansions as liquids—in other words, of 
reaching the same constant by a method analogous 
to that employed by Mendeléeff himself to the observ- 
ations of Kopp and Pierre. 
Mendeléeff’s work on the relative densities of aque- 
ous solutions of alcohol takes its place as a classic 
alongside the works of Blagden and Gilpin, and of. 
Drinkwater and Fownes in this country, and, as in 
the case of these observations, has been utilised by 
Continental Governments for the purposes of revenue. 
These determinations were applied by Mendeléeff to 
the elucidation of a theory of solution, and in a paper, 
also communicated to our Chemical Society, he sought. 
by means of them to reconcile Dalton’s doctrine of the 
atomic constitution of matter with modern views re- 
mon to all such works 
would be classed by 
are no books. 
