AND AMERICAN RURAL SPORTS. 



157 



The two general classes observe the same law in both of 

 their migratory instincts — the finding of food, and of fit 

 places for the rearing of their young. The general motion 

 for these two purposes is in opposite directions — they move 

 toward warmer regions in search of food, and toward colder 

 ones in order to build their nests. The winter birds come 

 to us for food, and the summer ones for nidification. The 

 winter ones never are those that feed upon land insects, and 

 but seldom those that feed upon seeds; because when they 

 come, there are few of these. They are chiefly water- 

 bii'ds, in some sense or other. They frequent the shores of 

 the seas, the inland lakes, or the margins of springs, rivu- 

 lets, and rivers, and they swim or wade, or merely run 

 along the bank, according to their nature; and resort to 

 those haunts where their food is to be found with the most 

 unerring certainty. They are all common inhabitants of 

 regions farther to the north, have reared their broods there, 

 and remained till the supply of food began to fail. The 

 extent of their flight southward depends upon the severity 

 of the winter; they come earlier, and extend farther, when 

 that is severe; and their departure is accelerated by a warm 

 spring, and retarded by a cold one. Though the diffusion 

 of the same species of birds be much more extended than 

 that of the same species of quadrupeds, there is still a va- 

 riation according to the longitude. The birds of passage 

 which appear in Britain are not exactly the same as those 

 either of continental Europe or of America; and that ac- 

 counts for the appearance of the occasional visiters. A 

 strong wind from the east, during the time of their flight, 

 often wafts a continental bird to our shores; and a strong 

 wind fi-om the west occasionally brings us an American 

 visiter. The flight of birds is, therefore, a sort of augury, 

 though a very different sort from that believed in by the 

 superstitions of antiquity. It has no connexion with the 

 ofiBces or fortunes of men, but it tells what kind of season 

 prevails in those climes whence the visiters come. The 

 early appearance of the winter birds is a sure sign of an 

 early winter in the northern countries; and the early 

 appearance of the summer ones is just as sure a sign of an 

 early and genial spring in the south. 



The migration of our winter visitants is a very simple 

 matter; we can easily understand why birds, when their 

 supply of food begins to fail, should fly off in a warm direc- 

 tion; but the return — the general migration northward for 

 the purpose of rearing their young, is, at first consideration, 

 a more difficult matter. Yet when we think a little, the 

 difficulty ceases, and the one movement becomes no more a 

 miracle or a marvel than the other. Very many of the 

 .summer birds feed upon insects; and summer insects are 

 more abundant in the northern regions than in the south. 

 This happens particularly with the water-flies, of which there 

 are supposed to be several generations in the course of a 

 Rr 



long summer's day; and the short night at that season occa- 

 sions little interruption to their production. The same 

 causes which produce the greater supply of insect food, in- 

 crease the daily period during which the bird can hunt, 

 and this gives it a farther facility of finding food, over 

 what it would have in the comparatively short days farther 

 to the south. But the breeding time is that at which the 

 birds are called upon for extraordinary labour. During the 

 period that the nest is building, there is a new occupation 

 altogether; and the nests, even of very small birds, are 

 constructed with so much care, that that and the finding of 

 subsistence demand more than the average power of indus- 

 try. When the female begins to sit on the eggs, the feed- 

 ing of her partially depends upon the male; and when the 

 young are hatched, their support, till they are in a condition 

 for supporting themselves, requires a considerable portion 

 of the time and industry of both parents. When the young 

 are fledged, the parent birds still require long days: the 

 operation of moulting, by which their tattered plumage is 

 replaced by a new supply, exhausts them: thus they have 

 long days, and also food in abundance, when they are least 

 able to make exertions in search of it; and by the time that 

 the decreasing supply warns them that it is time to seek 

 more southern climes, they are in prime feather and vigor- 

 ous health, and able to sustain the fatigues of the voyage. 

 The return, too, is, generally speaking, after the autumnal 

 equinox, so that in their migration southward, they have 

 the same advantage of a longer day than in places north- 

 ward. Thus, even in this common-place matter — a matter 

 which is so common-place that few take the trouble of heed- 

 ing it, and almost none inquire farther than saying that it 

 is the instinct of birds, — we may trace as perfect a succes- 

 sion of antecedent and consequent, or as we say, of cause 

 and effect, as in any other part of the works or economy of 

 creation. We ought, indeed, to guard very carefully 

 against stopping at the word instinct, or indeed at any other 

 word which is so very general that we cannot attach a clear 

 and definite meaning to it. Those general words are the 

 stumbling-blocks and barriers in the way to knowledge; 

 and when we turn to them who take upon themselves the 

 important business of instruction, and ask them for an ex- 

 planation, they but too frequently give us a word, and 

 when we get one, in our own language or in any other, to 

 which we can attach no meaning, the path to knowledge is 

 closed. Perhaps there are few words by which it is more 

 frequently closed than this same word, "instinct;" because 

 we are apt to rest satisfied with it as an ultimate or insulated 

 fact, and never inquire into that chain of phenomena of 

 which it forms a part. Now nothing in nature stands alone: 

 — Creation needs no new fiat; but the succession of events 

 throughout all her works depends on laws which are uner- 

 ring, because they are not imposed by any thing from 



