waders, especially the herons* and storks which 

 live in the midst of marshes and muddy waters, 

 where they find the food on which they live. 

 Every body may have observed how long they 

 will stand motionless arid in an erect posture ; 

 and many have doubtless wondered at the length 

 of time they can do so. This singular power, so 

 necessary to animals obliged to obtain their prey, 

 more by chance than industry, they owe to a pe- 

 culiar conformation of the articulation of the leg 

 and thigh. The articulating surface of the thigh 

 bone contains, in its centre, a depression, into 

 which is received a projection of the tibia. To 

 enable the animal to bend its leg, that projection 

 must be disengaged from the depression into 

 which it is lodged, and this is resisted by several 

 ligaments which keep the leg extended, in stand- 

 ing and flying, without the assistance of the 

 muscles. But it is only birds of this description 

 which are thus provided ; and all others are 

 obliged to employ muscular action when stand- 

 ing, except during sleep. In no instance has the 

 Almighty provided more organs than are abso- 

 lutely necessary to the well-being of the animal 

 He has created. 



The legs and feet of aquatic birds are wonder- 

 fully formed for accelerating their motion in that 

 element which is their greatest security. The 

 bone of the leg is sharp, and vastly compressed 

 sidewise ; and the toes, when the foot is brought 

 forward, close in behind each other, in such a 

 manner as to expose a very small surface in 



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