A.—MATHEMATICAL AND PHYSICAL SCIENCES. 25 
necessary to keep him from being disheartened by failure and to prevent 
the work from getting on lines which cannot lead to success.’ 
I should like to emphasise the last part of this quotation. A year or 
two spent on research under proper conditions is an educational training 
which cannot easily be overrated, but under others it may be positively 
harmful. It must always be borne in mind that the primary object of a 
University laboratory is not the same as that of a laboratory where there 
are no students in training, such as the National Physical Laboratory or 
the laboratory of a great firm. In such laboratories the main object is to 
get results, to discover as many new facts as possible. In a University 
laboratory the most important thing is to produce well-trained and well- 
educated men rather than to turn out the largest number of small papers. 
To get scientific results rapidly, the best plan is for the staff to select the 
subject for investigation, to determine the kind of experiment to be made, 
to exercise daily supervision over the work and to leave to the student 
little besides the taking of the observations. The intellectual develop- 
ment of the student is injured rather than benefited by a training like 
this. You cannot without disaster apply methods of mass production to 
education. Even in University laboratories where the importance of 
affording mental training is fully realised, over-specialisation is the great 
danger of these courses of research, and one that requires much care to 
avoid. The student gets so engrossed in his experiments that he grudges 
the time spent on going to lectures, or on reading books which are not on 
his own special subjects. He often spends too much time in making the 
experiments and too little in thinking about them. Sometimes, too, he 
neglects to take advantage of the opportunities afforded by a resident 
University for social intercourse with men of all shades of opinion and of 
experience. There is danger, too, of his getting into a groove and to go 
on working for the rest of his life on the particular subject on which he 
was first engaged. 
I think it helps one to get new ideas if the mind does not dwell too 
long on one subject without interruption, and if every now and then the 
thread of one’s thought is broken: It is, I think, a general experience 
that new ideas about a subject come when one is not thinking about it. 
I am not a psychologist and do not know the views held as to how new 
ideas originate, but to my mind there is considerable practical analogy 
between this process and one about which we have been hearing a good 
deal during the last few days, the induction of currents in a magnetic field. 
For this to occur change as well as the magnetic field is necessary. If a 
circuit is in such a field nothing happens as long as it is in repose, but if you 
disturb this repose, currents begin to flow through it. Now compare the 
circuit to the brain, the magnetic field to the state produced in the brain 
by long thought about a subject, the starting of a current to the starting 
of an idea. No ideas will come as long as the brain remains in the same 
condition without any change in its point of view, but if this changes, 
then currents or ideas are produced in the brain, the change as it were 
strikes sparks in the brain. This is one reason why I think it is desirable 
that the student should do a little teaching, another is that it would give 
him experience which may be valuable in after-life and help him to obtain 
a post. 
