18 LESSONS IN HORSE JUDGING. 



is made for additional cartilage by irregular bones 

 being interposed between the two ends of the long 

 bones (Fig. 2. jB), each of these bones being thickly 

 covered on its upper and lower surfaces, where 

 the concussion comes, by cai-tilage. So that in a 

 section from above downwards through the 'knee' 

 joint, instead of two buffers being interposed we 

 find six. The bone above the knee, and the bone 

 below it being in a straight line when the weight 

 of the body is thrown upon them, much concus- 

 sion would take place were it not for this arrange- 

 ment. When bones which meet and form a joint 

 are set at an angle, then of course there is less 

 chance of concussion, and so we find less ' carti- 

 lage ' needed. 



12. — As there are three forms of levers, we 

 must be careful to remember this, and we shall 

 close this somewhat dry and relatively uninter- 

 esting lesson by a few remarks on the mechanical 

 lever, and compare it with the animal lever. 



The lever is an unyielding bar (represented in 

 the animal by bone), capable of free motion about 

 a fixed axis, called the 'fulcrum.' To this lui- 

 yielding bar, ' power ' is applied (which in the 

 animal lever is represented by muscle and its ten- 

 don). Lastly, we have the weight, resistance, or 

 obstacle to be overcome by the power. 



If the fulcrum {F) be placed between the power 

 (P) and the weight (TF), so that when the power 

 sets the lever in motion the weight and the power 

 describe arcs, the concavities of wliich are turned 

 towards one another, the lever is said to be of the 

 fii^st order (See Fig. 3, A). If the fulcrum be at 



