386 BRAIN WORK AND 



If waste of time is characteristic of our methods 

 of teaching science, it is characteristic as well 

 of the methods used for teaching handicraft. 

 We know how years are wasted when a boy 

 serves his apprenticeship in a workshop ; but 

 the same reproach can be addressed, to a great 

 extent, to those technical schools which endea- 

 vour at once to teach some special handicraft, 

 instead of resorting to the broader and surer 

 methods of systematical teaching. Just as 

 there are in science some notions and methods 

 which are preparatory to the study of all sciences, 

 so there are also some fundamental notions and 

 methods preparatory to the special study of any 

 handicraft. 



Reuleaux has shown hi that delightful book, 



and if it is made clear, the pupils see at once that to suspend 

 two bodies of equal weight over a pulley, and to make them 

 move by adding a small weight to one of them, is one of the 

 means (and a good one) for slackening the motion during the 

 falling ; they see that the friction of the pulley must be reduced 

 to a minimum, either by using the two pairs of wheels, which so 

 much puzzle the text- book makers, or by any other means ; 

 that the clock is a luxury, and the " plates and rings " are mere 

 accessories : in short, that Atwood's idea can be realised with the 

 wheel of a clock fastened, as a pulley, to a wall, or on the top 

 of a broomstick secured in a vertical position. In this case the 

 pupils will understand the idea of the machine and of its inventor, 

 and they will accustom themselves to separate the leading idea 

 from the accessories ; while in the other case they merely 

 look with curiosity at the tricks performed by the teacher 

 with a complicated machine, and the few who finally under- 

 stand it spend a quantity of time in the effort. In reality, all 

 apparatus used to illustrate the fundamental laws of physics 

 ought to be made by the children themselves. 



