On Water and Air . 
[May, 
326 
for those great chasms which are sometimes very deep indeed. 
Now I want to propose a problem to you. There is a 
drawing of a glacier (Fig. 34), and you observe that black 
Fig. 34. 
mark on the farther side. That is a great moraine of the 
glacier cutting off the opposite side of the mountain. 
Now I want you to look at the glacier itself, and I hope 
you will answer the question that I shall propose. You see 
the crevasses sweep round in this way to form curves. I 
will ask the boys present to answer a question. The glacier 
runs along there. Will anybody tell me what is the direction 
in which the glacier is moving ? Is it to the right or to the 
left? [Voices : “To the left.”] I venture to say that we shall 
have in this assembly a majority of ten to one among the 
boys saying that that glacier moves to the right. It is as if 
the centre of the glacier pushed the ice forward, and the 
Fig. 35. 
sides held it back. You will now see that the answer which 
has been given is precisely the reverse of the truth. I 
