Mental and Physical Fatigue 93 



The World of Business. 

 Investigation might also be carried on in the sphere of 

 mechanical labour. Already some wonderful results have been 

 obtained in America at the great Bethlehem steel works. Three 

 hundred labourers had to shovel heavy iron ore, moderately heavy 

 earth, or light ashes. A scientific investigator suspected that the 

 reason better wcrk was not done might lie in the size of the shovels 

 used. The same size of shovel was used both for heavy ore and 

 light ashes. So the burden was sometimes so heavy that rapid 

 fatigue followed or the mass was so light that the workman's energy 

 was wasted. The investigator set out to find what were the ideal 

 sizes of spades for the different kinds of work to get the maximum 

 amount of work out of the men without undue fatigue. He first 

 discovered the exact weight which the average man could handle 

 best (21 lbs.), and afterwards the size of the shovels was varied 

 according to the material to give always approximately this weight. 

 Ten shovels of different sizes were designed. The most favourable 

 rest pauses were discovered by experiments, and the manager was 

 able to increase the output enormously, and so reduce his stafi'" 

 and increase wages. Each man now shovelled on the average 

 over 50 tons where he had shovelled 16 tons, and with no more 

 fatigue. 



Similar experiments were done in the lifting of pig iron. The 

 specially important part was found to be the right distribution of 

 rest periods. Por a certain weight of iron rest had to be 55 per 

 cent, of time ; for heavier, more ; for lighter, less. These were 

 therefore fixed for the workmen, who worked when the foreman 

 told them, and rested when the foreman told them, longer rests 

 being given when heavier weights were lifted. If the manager 

 had promised the men a bonus for extra work they would doubt- 

 less have rushed the work during the first few hours, and exhausted 

 themselves (c.f., men at Belfast works who worked three days and 

 three nights running to get extra pay) 



As it was, their work was quadrupled, their wages raised 60 

 per cent, and yet the management saved greatly by the change. 



It may well be questioned whether the custom of working 



