Essays / by Adam Smith.

  • Adam Smith
Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: Essays / by Adam Smith. Source: Wellcome Collection.

    468/482 page 462
    ^^62 THE SIGHT OF BIRDS IS PROMPT AND ACUTE. food into their bills, as the linnet and thrush feed theirs. Almost as soon as her chickens are hatched, she does not feed them, but carries them to the field to feed, where they walk about at their ease, it would seem, and appear to have the most distinct perception of all the tan- gible objects which surround them. We may often see them, accord- ingly, by the straightest road, run to and pick up any little grains which she shows them, even at the distance of several yards; and they no sooner come into the light than they seem to understand this lan- guage of Vision as well as they ever do afterwards. The young of the partridge and of the grouse seem to have, at the same early period, the most distinct perceptions of the same kind. The young partridge, almost as soon as it comes from the shell, runs about among long grass and corn; the young grouse among long heath, and would both most essentially hurt themselves if they had not the most acute, as well as distinct perception of the tangible objects which not only surround them but press upon them on all sides. This is the case too with the young of the goose, of the duck, and, so far as I have been able to ob- serve, with those of at least the greater part of the birds which make their nests upon the ground, with the greater part of those which are ranked by Linnaeus in the orders of the hen and the goose, and of many of those long-shanked and wading birds which he places in the order that he distinguishes by the name of Grallae. The young of those birds that build their nests in bushes, upon trees, in the holes and crevices of high walls, upon high rocks and precipices, and other places of difficult access; of the greater part of those ranked by Linnaeus in the orders of the hawk, the magpie, and the sparrow, seem to come blind from the shell, and to continue so for at least some days thereafter. Till they are able to fly they are fed by the joint labour of both parents. As soon as that period arrives, however, and probably for some time before, they evidently enjoy all the powers of Vision in the most complete perfection, and can distinguish with most exact precision the shape and proportion of the tangible objects which every visible one represents. In so short a period they cannot be sup- posed to have acquired those powers from experience, and must there- fore derive them from some instinctive suggestion. The sight of birds seems to be both more prompt and more acute than that of any other animals. Without hurting themselves they dart into the thickest and most thorny bushes, fly with the utmost rapidity through the most intricate forests, and while they are soaring aloft in the air, discover upon the ground the insects and grains upon which they feed. The young of several sorts of quadrupeds seem, like those of the greater part of birds which make their nests upon the ground, to enjoy as soon as they come into the world the faculty of seeing as completely as they ever do afterwards. The day, or the day after they are dropped, the calf follows the cow, and the foal the mare, to the field; and though
    digitised image 1
    digitised image 2
    digitised image 3