ie ONL he SEY ihre UI ed a Sp toa or ONE eS Rie ai a i a ca eg a in a Nn (ett 
x eee nie eee ee ws Sisees! 
JSean-Baptiste-André Dumas. 295 
Still, ‘the new mode of looking at the constitution of silicic 
is no ml 
acid slowly but surely gained ground, an 
rooted in our convictions, that the younger generation of chem- 
ists will scarcely understand the pertinacity with which this 
Innovation was resisted.’’* 
But if this investigation of gas and vapor densities brought 
a great strain upon the dualistic system, the second of the three 
great investigations of Dumas, to which we have referred, led 
to its complete overthrow. The experimental results of this 
_ Investigation would not be regarded at the present day as re- 
e, and cannot be compared either in breadth or intri- 
cacy with the results of numerous investigations of a similar 
character which have since been made. The most important 
of these results were the substitution products obtained by the 
action of chlorine gas on acetic acid. They were published in 
4 series of papers entitled “Sur les Types Chimigues,” and the 
Capital point made was that chlorine could be substituted in 
acetic acid for a large part of the hydrogen without destroying 
the acid relations of the products; and the inference was, that 
the qualities of a compound substance depend not simply on 
the nature of the elements of which it consists, but also on the 
blending of such opposite virtues. That chlorine should unite 
With hydrogen was natural, for no two substances could be 
more unlike; but that chlorine should supply the place of 
hydrogen in a chemical compound was a conception which the 
dualists scouted as absurd. Even Liebig, the “father of 
Tganic Chemistry,” warmly controverted the interpretation 
which Dumas had given to the facts he had discovered. Lie- 
big himself had successfally investigated the chemical relations 
of a similar class of organic products. He had, however, worke 
on the lines of the dualistic system, showing that organic sub- 
stances might be classed with similar inorganic substances, if 
Wwe assume that certain groups of atoms, which he called 
Compound radicals,” might take the place of elementary sub- 
Stances. In the edition of the organic part of Turner's Chem- 
'stry bearing his name, Organic Chemistry is defined as the 
Chemistry of Compound Radicals,” and the formule of 
* Hofmann, loc. cit. 
