348 DRIVING APPARATUS CH. XIV 



tendency of certain reins to slip more than others, 

 will be discovered by the expert in practising with 

 the weights. 



This apparatus can be simplified by substituting 

 for the pulleys and weights, india-rubber bands, 

 such as are sold by stationers for packages of 

 papers. Such a band, five-eighths of an inch wide, 

 and of a thickness of fourteen to the inch, will, 

 when somewhat stretched, give a resistance of 

 about a pound, and any number may be attached 

 to the end of the rein. This makes the apparatus 

 portable, and a hundred or more pulls upon it 

 every morning, when one has no opportunity of 

 driving, will keep the fingers and the arm in good 

 condition. 



