Page:Cassell's book of birds (IA cassellsbookofbi04breh).pdf/142

 behind?' issues from the leader, which is always replied to by some posterior Swan with an 'All's well!' vociferation. When the leader of the party becomes fatigued with his extra duty of cutting the air, he falls into the rear, and his neighbour takes his place. When mounted, as they sometimes are, several thousand feet above the earth, with their delicate outline scarcely perceptible against the clear blue of heaven, this harsh sound, softened and modulated by distance, and issuing from the immense void above, assumes a supernatural kind of tone."

The permanent habitat of the Swans is always upon large lakes of fresh water, or in marshy situations where fresh water is abundant. During their migrations, however, they take up a temporary residence on water of any kind. Their nests are generally placed on rivers or fresh-water lakes, but probably this is only on account of the shallowness of such situations, as after the breeding season some betake themselves to the sea, or wherever food is most abundantly procurable. The Swans are only active in the day, and even their migrations are never carried on by night. In their locomotive capabilities they surpass most other Swimming Birds. Their domain is the water, and it is only unwillingly that they ever venture on dry land; nor do they readily take wing, unless compelled to do so by unavoidable necessity. The very backward position of their legs renders walking on land difficult, so that when on dry ground their gait is heavy and vacillating. Their flight apparently requires considerable effort, more especially when they attempt to rise from the surface of the water; when, however, they have gained a certain altitude, it is extremely rapid. It would appear almost impossible for these birds to rise from the ground, and they never venture to alight on dry land. When beginning their flight from the water, they always stretch out their necks horizontally to their full length, striking the surface with their wings, and splashing with their broad-soled feet; and thus, half flying and half walking, they proceed for a distance of from forty to eighty feet, before they can acquire impetus to enable them to mount into the air. When, however, this is once accomplished, their movements are perfectly easy and free. When alighting from their flight they glide obliquely downwards to the water, and when they have nearly reached it, spread out their webbed feet to stay their headlong career, and moderate the shock of their descent. As relates to their vocal powers, different species of Swans vary considerably; some appear to be mute, but generally speaking their cry may be said to have somewhat the sound of a trumpet, and much resembles the voice of the Cranes. Some commonly, however, only utter a loud hissing or a low muttering noise; in other species, on the contrary, the voice is loud and powerful, and somewhat varied, so that when heard from a distance its effect is by no means disagreeable. The cry of the male is always louder and of a deeper tone than that of the female. The young "pipe," like young Geese. The manners of Swans are gentle, and rather shy, nevertheless they exhibit a certain degree of vanity and consciousness of power, often manifested in their domineering behaviour towards other Water-fowl. Only those of the same species associate in large numbers, and they seem particularly jealous of intruders. The matrimonial engagements of these birds are kept with exemplary fidelity, and last throughout their lives. No sooner have they paired, than the happy couple begin to show the tenderest affection towards each other, manifested by innumerable graceful caresses; they swim together with indefatigable constancy, and should danger approach defend each other with the utmost courage and self-devotion. Their care for their young progeny is equally remarkable. Although the male does not himself actually take a share in the duties of incubation, all his energies seem to be devoted to the protection of his mate during her patient retirement, and he may at such times always be seen, either swimming proudly and defiantly around her, or reposing in the immediate vicinity of the nest, as though to cheer her confinement by his presence. Although the labour of nidification seems to devolve principally upon the female, she is eagerly assisted by her mate, whose employment seems chiefly to be the procuration of materials, which he supplies abundantly, dragging them with his beak, sometimes from