230 FRA QMENTS OF SCI KNOW. 



significance imparted to them. The swing, the see-saw, 

 the tension of the giant-stride- ropes, the fall and rebound 

 of the football, the advantage of a small boy over a large 

 one when turning short, particularly in slippy weather; all 

 became subjects of investigation. A lady stands before a 

 looking-glass, of her own height; it was required to know 

 how much of the glass was really useful to her? We 

 learned with pleasure the economic fact that she might 

 dispense with the lower half and see her whole figure not- 

 withstanding. It was also pleasant to prove by mathe- 

 matics, and verify by experiment, that the angular velocity 

 of a reflected beam is twice that of the mirror which 

 reflects it. From the hum of a bee we were able to deter- 

 mine the number of times the insect flaps its wings in a 

 second. Following up our researches upon the pendulum, 

 we learned how Colonel Sabine had made it the means of 

 determining the figure of the earth; and we were also 

 startled by the inference which the pendulum enabled us 

 to draw, that if the diurnal velocity of the earth were 

 seventeen times its present amount, the centrifugal force 

 at the equator would be precisely equal to the force of 

 gravitation, so that an inhabitant of those regions would 

 then have the same tendency to fall upward as down- 

 ward. All these things were sources of wonder and de- 

 light to us: and when we remembered that we were gifted 

 with the powers which had reached such results, and that 

 the same great field was ours to work in, our hopes arose 

 that at some future day we might possibly push the subject 

 a little further, and add our own victories to the conquests 

 il ready won. 



I ought to apologize to you for dwelling so long upon 

 this subject; but the days spent among these young 

 philosophers made a deep impression on me. I learned 

 among them something of myself and of human nature, 

 and obtained some notion of a teacher's vocation. If there 

 be one profession in England of paramount importance, 

 I believe it to be that of the schoolmaster; and if there be 

 a position where selfishness and incompetence do most seri- 

 ous mischief, by lowering the moral tone and exciting 

 irreverence and cunning where reverence and noble truth- 

 fulness ought to be the feelings evoked, it is that of the 

 principal of a school. When a man of enlarged heart and 

 mind comes among boys when he allows his spirit to 



