PROBABLY the study of the methods of teaching the Classics has been handicapped by the predominant position which they long held in the curriculum of a liberal education. Other subjects were, each in its time, newcomers. They had to vindicate their claim to inclusion in the curriculum; and, in order to vindicate it, their supporters had to make clear to themselves and to others what was the special purpose in education which these studies were fitted to serve. The consciousness of this purpose naturally and properly influenced the consideration of the methods of teaching; and the teachers were not hampered by any time-honoured practices that had outlived their usefulness. In dealing with these subjects it was natural that a teacher should feel himself bound to think out his methods and free to try new ones. Thus, in the teaching of Natural Science within the last twenty years or so, the application of the heuristic principle has been reasoned out, formulated, put in operation, exaggerated, modified, and is now in a fair way to be co-ordinated, not unsatisfactorily, with other principles that cannot be disregarded.