close study has suggested a method, and for that preliminary study to be effective it must not be hampered by the thought of immediate practical returns. Had Darwin in mind the improvement of domestic races of pigeons and poultry instead of the explanation of their origin, he would have contributed much less than he did to be put to practical use. Therefore the farmer should cease to look upon biology as an expense and luxury meant to entertain rich men's sons; he should recognize that any laboratory that is helping to analyze the energies of life is contributing something, indirect but none the less important, to further our usage of plants and animals.
These views are by no means generally held; they have to be taught. To transmit the new ideas of each generation is the business of teachers, and we may now discuss what kind of men make the best kind of teachers. To this I would answer that, other things being equal, the investigator makes the best teacher. For the teacher's duty is not so much to inform as to interest, and the greater interest he has in his own subject the greater influence he will be likely to have over his pupils. Clearly, then, the investigator should teach well because he has the enthusiasm to undertake the difficult task of advancing his subject. Further than this, he can best treat his subject because he has won knowledge for himself as well as through others, he most fully realize the difficulties and problems, and he should be the least likely to pin his faith to unfounded theories. On the other hand, that teacher can not have great influence who has learned simply from his school and college courses and from text-books, and who has not tried to penetrate into the fascinating field that lies beyond. Louis Agassiz was the greatest teacher of natural science that this country has yet enjoyed, and he was through and through an investigator; take the example of any man whose students have been led to follow his profession, and you will find he was an original thinker. One man may be a very storehouse of detailed information, yet be unable to teach, for too much knowledge is an impediment to clear thought. Another may be ignorant of many things, which is really a desirable quality, and because of his creative spirit of research be an inspiring teacher. The teacher's business is not to drill his students so that they soak in facts like so many sponges; but he should give them the wish to blossom and break into fruit of their own. Were encyclopedic knowledge the ideal, one generation would receive the knowledge of the preceding, no more, and the centuries when such conditions prevailed were well termed the dark ages. The teacher should create as well as transmit, for creation strengthens his teaching quality. Thus it happens that in the long run it is pure science that is forwarding every movement in general education. We find a parallel in the case of musicians: there are many with a good technique, but very few with the power to com-