264 Mr Sang's Annual Report on the 



the development of knowledge, the study of the relations of phe- 

 nomena be needed, it must be that that branch of manufacture 

 which most calls for the exercise of mind, which substitutes mental 

 energy for brute force, is well fitted for expanding the intellect. 

 The due exercise of the physical organism is indeed essential to a 

 healthy state of mind ; yet those workmen whose employment 

 consists more in directing the energies of steam than in muscular 

 exertion, and whose business requires the combination of skill 

 and patience, stand in the most favourable situation as intellec- 

 tual beings. 



The mere direct application of physical strength in over- 

 coming resistance for which that strength is adequate, leads 

 slowly, if at all, to the expansion of the mind. But when the 

 resistance to be overcome far exceeds the strength of the indi- 

 vidual, or is of a kind to which his organs do not directly apply? 

 the powers of the intellect are rapidly called forth. 



Thus, we find among quarrymen, a thorough knowledge of 

 the properties of the lever, and considerable acquaintance with 

 the doctrine of the centre of gravity ; and among those work- 

 men who are employed about the railways in adjusting the po- 

 sitions of the waggons, an intimate acquaintance with the laws 

 of momentum. In witnessing the readiness with which their 

 knowledge is brought to bear on the matter in hand, we are very 

 apt to say, "It is merely the result of practice, of repeated 

 trial." True ! and what other was the knowledge possessed by 

 Galileo, Newton, or Lagrange ? The difference is not in kind, 

 but in degree. 



Suppose that a person whose mind has been trained to investi- 

 gation, who has learned the expeditious methods of inquiry now 

 in common use, were to begin his apprenticeship in any of these 

 employments, no one can doubt for a moment, that while his pre- 

 vious tuition will lend him prodigious assistance in accumulating 

 knowledge ; the practical or rather actual illustration continual- 

 ly before him, will give his mind a familiarity with the mecha- 

 nical laws which he could never have acquired from logical de- 

 ductions. 



On these general grounds, then, I think it reasonable to infer, 

 that the manipulation of planing engines and slide-lathes, is 



