32 MIND IN EVOLUTION CHAP. 



is, indeed, not a little instructive. Human ingenuity has 

 succeeded in mimicking one form of organic activity after 

 another. Up to a certain point the steam engine can be 

 made self-acting. We have already drawn attention to 

 the opening and closing of the valves by the piston as com- 

 parable to the rhythm of respiration. In speaking of the 

 pendulum, we might have referred to the " compensating" 

 arrangement whereby it is made to adjust itself so nicely 

 to differences of temperature that its length remains 

 approximately constant, though every portion of it ex- 

 pands. Here is an adaptation as remarkable in its way as 

 the vasomotor adjustments which maintain the even tem- 

 perature of the warm-blooded animal. If finally we were 

 to take refuge in the uniformity of machinery, and con- 

 trast it with the infinite capacity of the organism for 

 adjusting itself to the changing details of its surroundings, 

 which are never twice the same, if we urged that machinery 

 must always turn out the same pattern, and cannot 

 achieve individuality, our last card of this suit is trumped 

 by the linotype. No two consecutive lines of a book or a 

 newspaper contain the same number of words of the same 

 size. Hence the " spaces " required to bring the line to 

 the right length differ from line to line in a manner which 

 it is absolutely impossible to predict. There is no rule 

 and no uniformity in the matter. The human compositor 

 puts in the spaces as he sees that they are needed, and one 

 would say that this was a point at which the service of the 

 human eye could not be dispensed with. But, by a very 

 simple arrangement, the same end is achieved by the lino- 

 type, and with equal accuracy. 1 



bulk and the rapidity of its formation, and this in direct proportion to the 

 change in the conditions. If we change the conditions affecting an 

 organism, it will, up to a certain limit, adapt itself to the change, and 

 after, perhaps, an interval of disturbance, appear very much as it was 

 before. Its bulk, for example, will not uniformly increase or decrease in 

 direct proportion to its food supply. 



1 It is of some importance to notice the limitation of the achievement. 

 The number of spaces in the line is determined by the human compositor. 

 What the machine does is to thrust a wedge in between the words so as 

 to space them to the required length of the line. The method of response 

 given by the machine is unvarying. The variations are effected in 

 accordance with a plan by which the objects acted on, viz., the length of 

 the several words, determine the extent of the mechanical movement. 



