THE COMMON HEROX. 141 



weighs twelve ounces ; or the heron, estimated according to 

 the proportions of the owl, should weigh about four pounds 

 three ounces, while, as already stated, its weight is only 

 three pounds. Besides, the soft feathers of the owl take hold 

 of the air, and thus form a sort of fulcrum for the wings, by 

 means of which it can fly smoothly ; whereas the feathers on 

 the body of the heron are close, formed for throwing off rain, 

 something like those of a water-bird, and hence its body 

 takes no hold of the air. The wings of the heron are also 

 hollow, and take a strong hold, or rather meet with a strong 

 resistance in their downward stroke, so that, at every down- 

 ward stroke, the body of the bird jerks upward, as if there 

 were two joints, near the scapular articulation of the wings, 

 on which the lineal breadth of the bird played as on two 

 hinges. The hollow wing, which is of course as much con- 

 vex or raised on its upper side, enables the bird to raise it 

 with less effort than if it were more flat ; but still, there is a 

 jerk of the body downwards every time the wings are raised. 

 Thus the body of the bird see-saws or bobs through the air, 

 in a manner which is anything but graceful. 



But these peculiarities, though they give the heron what 

 may be considered as rather an ungainly style of flight, are 

 very useful to it in its habits, as a bird which is alternately 

 on high flight and fishing on the banks of the waters. The 

 hollow wings, assisted by the bending of the neck backwards, 

 which throws the centre of gravity rather on the rear of the 

 femoral articulation of the legs, jerk the body into the air 

 at the first stroke, so that it could take wing not only from 

 frail ground, but when it is standing in water up to the arti- 

 culation of the tarsi. 



Its pastures often lie far between ; and even from the 

 places in which heronries, or assemblages of nests, are some- 

 times built, it has to range for miles before it can find food 

 either for itself or its young : and as, in clear weather espe- 



