Poachers and Poaching. John F.L.S. Watson
also used in the case of a detachment being surprised by the enemy and not having time to send a telegram. For instance, when one or more pigeons arrive at the dovecote without despatches, and with the loss of some tail feathers, it is a sign that the troops have been attacked. Sometimes marks made with colour supply such-and-such information. Each detachment carries three or four pigeons in a light basket of bamboo and net. The distances being short, each despatch is sent by one pigeon. A first despatch is sent at the hour fixed in advance by the commander, the others successively as there is news to transmit. The pigeon-basket is borne by soldiers, who relieve one another at stated intervals. The grains of wheat and vessels of water are confided to a corporal, who has the care of the pigeons. When the detachment has to remain absent more than a day, they take with them four pigeons, with wheat and water in a leathern case. If they have to return in a day, they carry but three pigeons, with the food and drink necessary. The frequent arrival of these birds from all quarters presents a curious appearance. When they arrive they perch at the window of the dovecot, where their mates and young await them. To enter they must pass through a sort of cage-trap, which does not permit them to return, and at the same time separates them from the other pigeons. The weight of the newcomer sets an electric bell ringing; and this signal continues all the time the bird remains in the trap; thus giving notice to the sergeant of the guard, who takes the despatch and forwards it to headquarters.
The liability of so defenceless a bird as the pigeon to attack has led to experiments being undertaken from time to time with young ravens, which make fairly quick and reliable messengers up to a distance of about fifty miles. As the raven is very teachable (it can be made to "retrieve" most creditably), and as it manifests a strong attachment to its birth-place, there seems no reason why its training should not be further extended in the new direction, for which its great spirit and endurance appear eminently to fit it.
Here I have only touched upon the speed and power of flight, but the whole subject is one of the most fascinating branches of natural history. No reference has been made to the marvellous movements of birds in the air, which constitute the very poetry of motion—the stationary balancing, hovering, circling, and gliding, all of which may be observed, especially among our own birds of prey.
Although much is known of the speed of birds and animals, there are but few ascertained facts concerning that of insects and fishes. The comparatively low intelligence of these two classes of animals makes it difficult to direct them. They rarely fly or swim in anything approaching to a straight line, and experiments give only approximate results. Pike in pursuit of their prey seem to flash through the water; and salmon and trout move almost as quickly. The Spanish mackerel, with its smooth, cone-shaped body, is among the swiftest of fishes, and for speed only finds a parallel in the dolphin. There is a great similarity in shape between these two, and both cut the water like a yacht. The first follows the fastest steamers with the greatest ease, in its dashes swimming at five times their speed. The bonito is also a fast swimmer; and all those fishes "trimmed" in like fashion with him.
There is one insect to which attention may be drawn, as affording a most striking example of speed among lowly-winged creatures. That is the dragon-fly. I have frequently had an opportunity of dropping into company with the largest species (Libellula grandis), in its aerial excursions in autumn by a particular roadside, along which there was a rushy-margined pool. At such times the writer has been occasionally on foot,—more frequently driving. On foot one has scarcely any means of judging of its speed, for in a moment it is past and gone out of sight. But what is the experience when you are driving, say at ten or twelve miles an hour? This rapid voyager passes over, proceeds beyond you almost out of sight, then turns, swerving widely from right to left, repasses again in both directions, traversing repeatedly the ground, while you are travelling, or rather dragging, over the same space of about a mile only once. We are apt to exaggerate in these matters, but with every allowance, having compared the flight of a dragon-fly with that of a passing hawk, swallow, or cuckoo, I have computed that this large species is capable of flying at a speed of from eighty to one hundred miles an hour—an enormous draw upon the creature's nerves and muscular powers, as manifested by occasional rests of a few minutes upon a bush or a piece of sedge, its habits not requiring uninterrupted flight at such a pace. Perhaps the need of these occasional rests is an erroneous opinion founded upon too limited an area of observation. For Cuvier has stated that M. Poey, who had particularly studied the insects of Cuba, informed him that at certain seasons of the year the northerly winds bring to the city of Havannah and its neighbourhood an innumerable quantity of specimens of one of the species of Libellulæ. Other instances of the periodical flights or migrations of dragon-flies have been noted by observers. And even butterflies have been seen to migrate to distant points of land, making flights of fifty or sixty miles across water. These long journeys may be relieved by occasional rests, as Mr. Newman and others have ascertained that lepidopterous insects are able to alight upon the water, rest awhile, and then rise with apparent ease—a fact readily credited by fishermen, who so frequently see the green-and-grey drake and other ephemeræ float down stream, and, if not taken by the trout, suddenly spring up again, and resume their aerial dances. But this power of rapid movement in the dragonfly, be the rate more or less, is in just keeping with its structure. The insect's body is slender, the chest strongly developed, though firm; the wings, four in number, are narrow, of great length, and consist of fine, thin, dry membrane, stretched upon a series of lightly made costæ, or rafters. No wonder, then, that with such a mechanism the creature pursues its prey of smaller insects with such rapidity.
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