148 CAPITAL THE MOTHER OF LABOUR iv 



in the purple get off with a lighter task than the 

 child who first sees light under a hedge. 



How is it that the new-born infant is enabled 

 to perform this first instalment of the sentence 

 of life-long labour which no man may escape ? 

 Whatever else a child may be, in respect of this 

 particular question, it is a complicated piece of 

 mechanism, built up out of materials supplied by 

 its mother ; and in the course of such building- 

 up, provided with a set of motors the muscles. 

 Each of these muscles contains a stock of sub 

 stance capable of yielding energy under certain 

 conditions, one of which is a change of state in 

 the nerve fibres connected with it. The powder 

 in a loaded gun is such another stock of substance 

 capable of yielding energy in consequence of a 

 change of state in the mechanism of the lock, 

 which intervenes between the finger of the man 

 who pulls the trigger and the cartridge. If that 

 change is brought about, the potential energy of 

 the powder passes suddenly into actual energy, 

 and does the work of propelling the bullet. The 

 powder, therefore, may be appropriately called 

 work-stuff, not only because it is stuff which is 

 easily made to yield work in the physical sense, 

 but because a good deal of work in the economical 

 sense has contributed to its production. Labour 

 was necessary to collect, transport, and purify the 

 raw sulphur and saltpetre ; to cut wood and con 

 vert it into powdered charcoal ; to mix these in- 



