introduced by botanists, but originated in practical life and passed over from the popular vocabulary into our science.
The first demonstrable beginnings of plant physiology we find among the Greek philosophers, chiefly Aristotle and Theophrastus. But in these beginnings there was no developmental capacity. In our inductive developmental period it was necessary to lay a new foundation for the doctrine of plant life. The Englishman, Stephen Hales, in the beginning of the eighteenth century, was undoubtedly the founder of plant physiology in general, and especially the founder of physical plant physiology, while the commencement of chemical plant physiology is to be referred to the Hollander, Ingenhouss. Ingenhouss is closely identified with us in this regard, that for years he resided in Vienna as physician of the Empress Maria Theresa and of Emperor Joseph II. Some of his first contributions to plant physiology were worked out in Vienna—a fact little known. Later, until the middle of this century, the science was advanced by investigators of French nationality, foremost the Swiss investigator, De Saussure. At the present time, all civilized nations, the Japanese not excluded, take part in the advancement in this field. But if in our time names like De Saussure and Boussingault stand as towering monuments and the teachings of Darwin cease not to influence our physiological conceptions, there have been for many decades German plant physiologists who stood not simply as compeers of their French and English colleagues, but without exaggeration one may venture to say that German investigators have assumed the leading role in the solution of the most important questions.
The present developmental period in natural sciences, so rich in unprecedented results, is characterized by the inductive method of research and by the principle of the division of labor. It required thousands of years to show mankind that the experience of all knowledge takes root, and that the human mind, with its limitations, despite the genius of occasional great men, can only by the combined work of many, each deep in his narrow specialty, arrive at the solution of the great problems of science. As a consequence, we see in all fields of research the modern socialism of scientific progress vanquishing the intellectual giants of the olden time.
The objections to the principle of the division of labor in behalf of the mental stage of the individual are well known. These are gradually disappearing, and I will leave them without discussion. But for the development of science all of the weaknesses and failures resulting from this principle will be eradicated, as I shall later demonstrate by certain examples at hand.
In the realm of botany the division of labor brought about first a separation of descriptive botany from the studies directed toward general morphology and physiology, which latter, reenforced in a measure, placed themselves in rather sharp opposition to the descriptive side.
