The method of scientific teaching has been peculiar from the beginning. It is the most energetic form of what may be called the _repetitorial_ system, a method of teaching almost peculiar to France, and which may be described as a very able combination of professional and tutorial teaching. The object of the _répétiteur_, or private tutor, is to second every lecture of the professor, to explain and fix it by ocular demonstration, explanations, or examination. This was a peculiarity in the scheme of Monge and Foureroy. The latter said, in the first programme, “Our pupils must not only learn, they must at once carry out their theory. We must distribute them into small rooms, where they shall practice the plans of descriptive geometry, which the professors have just shown them in their public lectures. And in the same manner they must go over in practice (_répéteront_) in separate laboratories the principal operations of chemistry.” To carry out this system the twenty best pupils, of whom M. Biot was one, were selected as _répétiteurs_ soon after the school had started. Since then the vacancies have always been filled by young but competent men, aspiring themselves to become in turn professors. They form a class of teachers more like the highest style of private tutors in our universities, or what are called in Germany _Privat-docenten_, than any other body--with this difference, that they do not give their own lectures, but breaking up the professor’s large class into small classes of five and six pupils, examine these in _his_ lecture. The success of this attempt we shall describe hereafter. 2. A change may be noticed which was effected very early by the Council of Improvement--the union of pupils for artillery and engineers in a single school of application. The first report in December 1800, speaks of the identity in extent and character of the studies required for these two services; and in conformity with its recommendation, the law of the 3rd of October 1802, (12th Vendémiaire, XI.) dissolved the separate artillery school at Châlons, and established the united school for both arms in the form which it still retains at Metz.