148 mr. darwin's work and 



function, between mechanism and w T ork. Function is 

 the expression of molecular forces and arrangements no 

 doubt ; but, does it follow from this, that variation in 

 function so depends upon variation in structure that the 

 former is always exactly proportioned to the latter ? If 

 there is no such relation, if the variation in function 

 w T hich follows on a variation in structure may be enor- 

 mously greater than the variation of the structure, then, 

 you see, the objection falls to the ground. 



Take a couple of watches — made by the same maker, 

 and as completely alike as possible ; set them upon the 

 table, and the function of each — which is its rate of 

 going — will be performed in the same manner, and you 

 shall be able to distinguish no difference between them ; 

 but let me take a pair of pincers, and if my hand is 

 steady enough to do it, let me just lightly crush to- 

 gether the bearings of the balance-wheel, or force to a 

 slightly different angle the teeth of the escapement of 

 one of them, and of course you know the immediate 

 result will be that the watch, so treated, from that mo- 

 ment will cease to go. But what proportion is there 

 between the structural alteration and the functional 

 result ? Is it not perfectly obvious that the alteration 

 is of the minutest kind, yet that slight as it is, it has 

 produced an infinite difference in the performance of 

 the functions of these two instruments ? 



Well, now, apply that to the present question. 

 What is it that constitutes and makes man what he is ? 

 What is it but his power of language — that language 

 giving him the means of recording his experience — 

 making every generation somewhat wiser than its 

 predecessor, — more in accordance with the established 

 order of the universe ? 



