SCIENTIFIC CULTURE. 585 



lioweyer, an advantage to be gained in subsequently reviewing the 

 subject as presented in a good text-book, and such a book may be of 

 great use iu preparation for an examination. But how far examina- 

 tions are of value in enforcing the acquisition of knowledge of an ex- 

 perimental science is a question on which I feel a grave doubt. Cer- 

 tainly their value is very small if, as is too frequently the case, they 

 lead the student to defer all effort to make his own the knowledge 

 presented in the lectures, until a final cram. 



The management of lectures, text-books, and examinations, will 

 not, however, offer nearly so great difficulties to the teacher as the 

 management of the parallel experimental course of laboratory teach- 

 in 2^. In the last the methods are less well tried and demand of the 

 teacher a very considerable amount of invention and experimental 

 skill. To follow mechanically any text-book would result in a loss of 

 the proper spirit with which the course should be conducted and which 

 constitutes its chief value. No experiments are so good as those which 

 have been devised by the teacher, or, still better, by the pupils them- 

 selves. A mere repetition of a process, according to a definite descrip- 

 tion, has no more value than a repetition of a form of words in an 

 ordinary school recitation. The teacher must make sure that the stu- 

 dent fully understands what he is about, and comprehends all the con- 

 nections between observations and conclusions which it is his aim to 

 establish. Moreover, he must constantly encourage his students to 

 think and work for themselves, and direct them in the methods of in- 

 ductive reasoning. The failure of an experiment may be made most 

 instructive if the student is led to discover the cause of the failure. 

 A leak in his apparatus may be turned to a similar profit if the student 

 is shown how to discover the leak, by carefully eliminating one jDart 

 after another until the weak point is made evident. 



The direction of an experimental laboratory is no easy task. The 

 teacher must make each man's work his own, and follow his processes 

 of thought as well as his experiments with the most careful attention. 

 TVith large classes much time can be saved by going through each 

 process on the lecture-room table and giving the directions to the class 

 as a whole ; but this does not supersede the personal attention and in- 

 struction which each student requires at the laboratory table. More- 

 over, in laboratory teaching the teacher must rely, as we have said, on 

 his own resources, and but few aids can be given. There are books, 

 however, which will help the teacher to prepare himself for his work, 

 and I am happy to say that a book entitled "The New Physics," 

 prepared by my colleague. Professor Trowbridge, is now being printed, 

 which I hope will greatly promote the laboratory teaching of phys- 

 ics. Nicholl's abridgment of Eliot and Storer's " Manual " has long 

 served a similar valuable purpose in chemistry, and there are many 

 excellent works on " Qualitative Analysis," a study which is admirably 

 adapted to develoj) the power of inductive reasoning. 



