380 THE CANADIAN NATURALIST. [^^^l. vii. 



atoms of this powerful element were ranged on the side of oxygen, 

 both being invariably found in binary combinations of which 

 they formed the electro-negative element, the atoms of carbon 

 and hydrogen constituting the electro-positive radical. 



Thus the great promoter of inorganic chemistry attempted to 

 fashion organic molecules according to the image of those mole- 

 cules of dead matter which he had studied so thorouschlv. The 

 paths which Lavoisier traced in this domain he wished to extcod 

 to the world of products formed under the influence of life; they 

 resulted in a dead-lock. In proportion as the riches of science 

 increased it was necessary, in order to uphold the system, to 

 accumulate hypotheses, to invent radicals, to construct, with in- 

 sufficient or imaginary data, formulas more and more complicated 

 — a thankless task, in which the feeling of experimental realities 

 and sober appreciation of facts often gave place to outrageous 

 reasonings and vague subtleties. These barren efforts of a great 

 mind inaugurated the decline or marked the termination of the 

 dualistic ideas which were at the foundation of what has been 

 called, improperly perhaps, the old chemistry. The new began 

 at that point. Great discoveries, cleverly and boldly interpreted, 

 gave it an impulse which still endures. 



There were then — I speak of forty years ago — a number of 

 young men, with Dumas and Liebig at their head, in the oppo- 

 site camp, who cultivated with ardour the investigation of organic 

 compounds. Convinced that the constitution of these compounds 

 could only be deduced from the attentive investigation of their 

 properties and metamorphoses, they undertook to investigate 

 these bodies themselves, to transform them, to torment them in 

 some sort by the action of the most diverse reagents, in the hope 

 of discovering their intimate structure. And this is, gentlemen^ 

 the true method in chemistry ; to determine the composition of 

 bodies, and by careful analysis of their properties to fix, as fai* 

 as possible, the grouping of their ultimate particles. This, then^ 

 is the glory of our science, and the single but precious contribu- 

 tion which it is able to furnish for the solution of that eternal 

 problem, the constitution of matter. 



From the researches which were made at this epoch and m 

 this spirit, an all-important fact issued ; it relates to the action' 

 of chlorine on organic compounds. This simple body deprives 

 them of hydrogen and may be substituted for that element, atom 

 for atom, without affecting the molecular equilibrium and with- 



