TBE ANGLE OF TRACTION, ETC. 227 



being thrown to a great extent on the horse's back, 

 under the then prevalent notion that there is a great 

 advantage gained by bringing a horse as nea7' to his 

 work as possible. But a great oversight has been 

 committed, or rather a great many of us have forgotten 

 to think at all about the matter, and have gone on 

 using hames and collars that were constructed to be 

 used with shafts that hung in a horizontal position at 

 best, w^hereas they are now triced up sometimes 1 foot 

 higher at the point, with the same height of wheel, 

 forming an angle of from lO** to 15° with the hori- 

 zon. This has in innumerable instances inverted 

 the angle of traction, so to say ; and the line of the 

 trace, which was intended to be horizontal in accord- 

 ance wdth the mathematical theory, now descends from 

 its point of attachment on the shaft to the joint of the 

 collar, so that instead of forming a right angle with the 

 collar and shoulder-blade it forms a very acute one 

 with both. No doubt we have thus taken the load off 

 the horse's back, but w^hat we have done with the 

 poor animal's neck and shoulders is shown by fig. 1 7, 

 which is, we are sorry to say, anything but an exag- 

 geration, or an exception to what daily comes under our 

 observ^ation. This figure scarcely requires an explana- 

 tion, s s represents the shaft tilted up, a shows the 

 angle of traction with a short trace, such as is used in 

 carts, and h h that of the long one used in gigs ; and it is 

 quite evident that, with both one and the other, every 

 effort made by the horse tends to make the collar slip 

 upwards in the direction of the arrow T with the short 

 trace a much more decidedly than with the longer one 

 h h ; and this not only involves a proportionate loss of 

 power, to counteract which the horse is compelled to 



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