March 25, 1904.] 



SCIENCE. 



485 



more than merely unify the subject; it 

 placed in the hands of the teacher the pos- 

 sibility of making a really simple and log- 

 ically-arranged presentation of his subject, 

 a presentation which had been in vogue 

 among the classicists for many years, and 

 possibly the only presentation which could 

 make the experimental study of physics a 

 genuine training for power. 



In the domain of higher physics, the 

 work of J. J. Thomson, in 1887, on the 

 'Application of Dynamics to Physics and 

 Chemistry' may fairly be considered as 

 marking an epoch in the energy treatment 

 and in the unification of physical science. 

 Equally impressive are the three volumes 

 containing the proceedings of the Interna- 

 tional Congress of Physicists at Paris in 

 1900. One turns the entire two thousand 

 pages of this report without feeling the 

 slightest discontiniiity either of subject or 

 of method, from the dynamical papers at 

 the beginning to the electrical papers at 

 the end. 



2. Introduction of the Student Labora- 

 tory.— But of all reforms in method the 

 most revolutionary was the introduction of 

 the student laboratory, which came in at 

 about the same time with the energy treat- 

 ment. 



To be sure, especially favored students 

 have always been admitted to the private 

 workshop of the master, but it is only 

 within the last generation that students in 

 general have obtained similar privileges. 



In a letter to Nature, dated January, 

 1871, Professor E. C. Pickering describes 

 the new physical laboratory of the Massa- 

 chusetts Institute of Technology, where he 

 was then an instructor, and proceeds to 

 add: 'There are now in America at least 

 four similar laboratories either in operation 

 or in preparation and the chances are that 

 in a few years this number will be greatly 

 increased. ' 



How amply this prediction has been ful- 



filled may be realized when we consider that 

 America has to-day more nearly four hun- 

 dred fairly equipped physical laboratories. 



In this connection it is well for those of 

 us who are inclined to be optimistic to turn 

 now and then to Professor Pickering's 

 'Physical Manipulation,' the only English 

 laboratory manual available in my under- 

 graduate days, and see how thoroughly 

 modern his treatment remains. Confess- 

 edly the problems are not graded exactly 

 as we should do it to-day, yet in spirit, in 

 method, in economy of teaching energy and 

 in sound learning these two volumes may 

 well give us paiise, and make even the most 

 sanguine ask whether evolution is not a 

 provokingly tedious process. 



Let no one infer, however, that improve- 

 ments in method are entirely illusory, for 

 the present-day instructor in physics cer- 

 tainly has in mind more clearly than any 

 before him just what the goal is and just 

 what the method of approach. He knows 

 full well that no student can work out his 

 own salvation while seated in a comfortable 

 auditorium chair, observing a speaker man- 

 ipulate certain curious apparatus with cer- 

 tain curious effects. 



3. Lessons Learned from the Engineer. 

 — The modern instructor has learned also 

 to take advice from the engineer— this too 

 without bowing to the immediately useful 

 and without substituting mere knowledge 

 for intellectual power. He realizes that 

 centrifugal forces, centrifugal couples and 

 the energy of rotation may quite as well 

 be studied from bicycles and the driv- 

 ing wheels of a locomotive as from an 

 ellipsoid strung on a knitting needle. 

 Electrical science and electrical engineer- 

 ing were at one time much farther apart 

 than they are to-day ; the engineer and the 

 physicist are closer friends than they were 

 twenty-five years ago. 



Perhaps neither all the phariseeism nor 

 all the charity has been confined to one 



