ABSTRACT
The science of modern chemistry has been created during the present century, but its phenomena and laws are so complex that it presents only a few of those great discoveries which are the starting-points for new developments, and which can, at the same time, be popularly described. The most important of all—that which constitutes the very foundation of chemistry as a science—is the law of chemical combination in multiple proportions, together with the atomic theory which serves to explain it. The determination of termed cases of isomerism and polymerism and their hypothetical explanation by the diverse arrangements of their constituent atoms form a special department of modern chemistry. One of the most recent advances in the philosophy of chemistry is exhibited in the views of the Russian chemist, Mendeleef, as to the natural arrangement of the elements with certain deductions from it.
