which should always be strictly attended to, it received no food at all on the morning of its liberation at Oban. The house-pigeon, however, is useless except for comparatively short distances, and even then is never to be much depended upon. His extreme domesticity predisposes him to pay a visit to every dovecot on the route, and to fraternise with every flock of brother pigeons he may happen to fall in with. His peculiar mode of flight, besides, and his extreme timidity, mark him out as an easy and desirable prey for any keen-eyed hawk or falcon that may be at the moment impransus, as Johnson in his early days once signed a note in London--dinnerless. The common pigeon, too, wings his flight at a comparatively low altitude, and becomes an easy shot to any one with a gun ready to hand when it passes by. Not so the true carrier pigeon, which flies at a great height, far out of range of needle-gun or artillery--out of range of human sight, in fact; so that it is never in danger of being brought to grief, as was poor Gambetta in his balloon when passing above the Prussian lines the other day. The velocity with which some birds fly is almost incredible. A hungry falcon, with his blood up and in eager pursuit of his quarry, will fly at the rate of 150 miles an hour, and keep it up too until his object is attained; and the tremendous impetus of the bird at such a speed accounts for the dreadful wounds that a falcon inflicts when it strikes its prey, sometimes ripping up a grouse, or blackcock, or mallard, from vent to breastbone, as if it had been done by the keen edge of a butcher's cleaver. A goshawk (Falco palumbarius) belonging to Henry of Navarre--the Henri Quatre of after days--having its royal owner's name engraved on its golden varvels, made its escape from Fontainebleau in 1574, and was caught in Malta within four-and-twenty hours afterwards--a distance of 1400 miles, or at the rate of sixty miles an hour, supposing him to have been on the wing the whole time. But a hawk never flies by night, so that, on a fair computation, the bird's speed in winging the enormous distance must have been at the rate of at least 100 miles an hour. We have calculated that a snipe, thoroughly alarmed, and going its best, can fly at the rate of a mile a minute, and there are other well-known birds equally fleet of wing. Nor must it be supposed that the velocity of birds is a mere "flash-in-the-pan," so to speak--a "spurt," as it were--which could not be kept up. The long-sustained flights of migratory birds proves the contrary--that birds are not only inconceivably fleet, but, to use a racing term, that they can stay as well. Of our more familiar birds, we should say that the common wild duck of our meres flies with greater velocity than any other bird with which the reader is likely to be well acquainted. CHAPTER XVII.