APPENDIX II. 



161 



though not quite so conclusively. To illustrate 

 this I will here give a summary of three sets of 

 experiments : the first, made by Dr. E. Smith, upon 

 prisoners engaged in treadmill labour ; the second, 

 by the Eev. Dr. Haughton, upon military prisoners 

 engaged in shot drill ; and the third, adduced by 

 Playfair, and made upon pedestrians, piledrivers, 

 men turning a winch, and other labourers. 



TREADWHBEL EXPERIMENTS. 



A treadwheel is a revolving drum with steps 

 placed at distances of 8 inches, and the prisoners 

 are required to turn the wheel downwards by step- 

 ping upwards. Four prisoners, designated below 

 as A, B, C, and D, were employed in these experi- 

 ments, and each worked upon the wheel in alternate 

 quarters of an hour, resting in a sitting posture 

 during the intervening quarters. The period of 

 actual daily labour was 3^ hours. The total ascent 

 per hour 2160 feet, or per day 1-432 mile. The 

 following are the results : 



Treadwheel Work. (E. Smith.) 



