U JUDGING HOUSES 



muscles of the jaw apply their power to the center of the 

 jaw bone, the f alcrum is at the point where the under jaw 

 joins the head, while the application of the power is at the 

 teeth. 



2. Action of the Muscles. In considering the leverage, 

 the attachment of the muscles arid their nature are impor- 

 tant. As the muscles consist of bundles of fibres, it is easy 

 to understand that when these fibres are long, they possess 

 more elasticity than when they are short. The long muscle 

 with long leverage, added to by length of the bones is more 

 favorable for quick action or speed, while the heavier mus- 

 cle is more favorable for draft or power. The attachment 

 of the muscles to the skeleton is also an important feature. 

 When the muscles by means of the tendons are attached to 

 prominences thus enabling them to work some distance 

 from the bones that furnish the leverage, it is easy to see 

 that the action of the muscles would be more effective. 

 Hence, in most joints there are prominences to give the 

 muscles the most favorable attachment. 



In this connection it will be interesting to study the pro- 

 portions of the bones of the skeleton to find reasons for the 

 advantages which are supposed to originate with different 

 proportions. In general we look for short bones in those 

 parts where the function is simply the transmission of 

 power ; while we desire greater length in those parts where 

 the muscles, the source of power or speed, are to be found. 

 In the front leg for instance it is desirable to have the 

 distance long from the elbow to the knee, with the propor- 

 tions showing a much greater distance than from the 

 knee to the fetlock joint for the reason that the distance 

 over which the power travels should be as short as pos- 

 sible that it may be economized and but little of it lost 

 in transmission. 



3. Function of the Nervous System. In studying the 

 horse as a mechanism, more than bone and muscle should 

 be included. The stimulation for action comes from the 

 nerve power or force. The nerve power is represented 



