TEACHING AND LEARNING 9 



from discussion with his students, nor refuse to learn from them. 

 Finally, he is not discouraged by the inevitable discrepancy 

 between his ideals and his results, but, remembering that aver- 

 ages and not extremes count in the long run, he presses cheerfully 

 on, profiting by experience and building for the future. 



There is one accompaniment of good scientific teaching 

 which fully deserves the great emphasis it often receives, and 

 that is the doing of some investigation by the teacher. The 

 dominant idea in all scientific teaching, from the kindergarten 

 to the university, should be the inculcation of the spirit of inves- 

 tigation, the instinct to attack new problems with a deter- 

 mination to solve them by one's own efforts. Only the teacher 

 who feels this spirit can impart it, and only he can feel it who 

 is ever exercising it. For university and most college work 

 this is now viewed as axiomatic, but it is true in principle for 

 all grades of teaching. For most teachers, however, as well 

 those in many colleges as in most schools, the limitations of 

 training or equipment, or the demands of the teaching, which 

 itself is properly entitled to the teacher's first and best efforts, 

 effectually prevent any investigation of the abstract scientific 

 sort. It is very fortunate, therefore, for the teacher of this sub- 

 ject, that there lies open an attractive and profitable field of 

 investigation in the educational phases of the subject itself. 

 As the following pages will show, some of our physiological 

 experiments, appliances, and methods are educationally satis- 

 factory, being accurate, practicable, and profitable; but others, 

 including still the majority, are imperfect and susceptible of 

 great improvement. Again, in only a few cases do we know 

 which of the accessible plants are best for the study of a particu- 

 lar subject, or. in just what way they should be treated to yield 

 the best results, or how much, quantitatively, may be expected 

 of them; and there is much to be done in this direction. Further, 

 the extreme specialization of science, and the consequent inac- 

 cessibility to general students of most of its later results, are 

 giving a positive value to good . comprehensive expositions of 

 scientific topics, such expositions as combine literary excellence 



