shadow cast by his load of corn, the country-side stares all parched and cracked and gasps for a rainy breeze. The kestrel hovers just the same. Could he not do so, a long calm would half starve him, as that is his manner of preying. Having often spent hours in trees for the purpose of a better watch upon animals and birds, I can vouch for it that ascending currents are not frequent—rare, in fact, except in a gale. In a light air or calm there is no ascending current, or it is imperceptible and of no use to the kestrel. Such currents, when they do exist, are very local; but the kestrel's hover is not local: he can hover anywhere. He can do it in the face of a stiff gale, and in a perfect calm. The only weather he dislikes is heavy thunder, rain, or hail, during which he generally perches on a tree; but he can hover in all ordinary rain. He effects it by sheer power and dexterity of wing. Therefore if the fact has any bearing upon the problem of flight, the question of currents may be left out altogether. His facing the wind is, as has been pointed out, only a proof that he is keeping his balance.
The kestrel is not the only bird that hovers. The sparrowhawk can. So can all the finches, more or less, when taking seeds from a plant which will not bear their weight or which they cannot otherwise get at; also when taking insects on the wing. Sparrows do the same. Larks hover in their mating season, uttering a short song, not the same as when they soar. Numerous insects can hover: the great dragon-fly will stop dead short in his rapid flight, and stay suspended till it suits him to advance. None of these require any current or wind. I do not think that hovering
