THE BONES. 



39 



human figure it is at once seen to be the knee, and on referring 

 to the same letter in the leg of the bird, we shall find that it 

 is the true knee also ; for supposing it to kneel, that is, to 

 bend its leg, so that the fore part of the joint should touch 

 the ground, it can only do so at the joint B, it being as 

 obviously impossible from the structure of the joint c, that it 



could bend the part c D forwards, so as to make the front part 

 of the joint c touch the ground, as it would be for us to bend 

 the leg-bone forward below the knee. The remaining portion, 

 then, c D, of the bird's limb, when compared with the similar 

 part in our own leg, ought to be called its ankle, and so in 

 truth it is. This may be more easily understood by referring 

 to a very extraordinary-looking bird, sometimes, though very 

 rarely, seen in England, called the Black-winged Stilt, from 

 the strange disproportion of its legs, a figure of which is 

 annexed, and of which No. 2 may be considered as an illustra- 

 tion ; in which an inexperienced observer will at first sight not 

 easily persuade himself that c D is nothing more than the ankle, 

 and the back part of the joint c its heel ; yet so it is, as the 

 reader will at once perceive in the following figure, where the 



