B I R 
provide their brood a more fecure retreat. When 
l;]ie whole family are fully plumed, and capable 
of avoiding danger, they are led forth in fine 
weather, and taught the art of providing for their 
own fubfiftence, by being conduced to thofe places 
where their food is moft likely to be found : they 
are alfo at the fame time inftru(5led in the method 
of picking it up, and carrying it away; and are 
then re-condu6led to the neft, where they continue 
a day or two longer. At length, when they are 
fully qualified to fhift for themlelves, the old ones 
again take them abroad; and, after leading them 
to the accuftomed places, leave them to ihift for 
themfelves; and all conne(5lion ceafes. 
Thofe Birds which are hatched earlleft in the 
feafon are the ftrongeft and mod vigorous ; while 
fuch as have been delayed till the middle of 
fummer are more tender and feeble, and fome- 
times incapable of fuftaining the rigours of the en- 
fuing winter. The very Birds themfelves leem 
to be fo fenfible of this difference, that they en- 
deavour to breed early in the fpring; but, if their 
endeavours are obftrufted, by having their nefts 
fobbed, or by any other accident, they ftill perfe- 
vere in their efforts for a progeny ; and it Ibme- 
times happens that they are retarded by a variety 
of accidents even to the middle of winter. "What 
number of eggs a Bird is capable of laying in one 
fealbn, has never yet been afccrtained ; but it is 
certain that fuch as would have laid but two or 
three at the moft, if their nefts be robbed, or their 
eggs ftolen, will lay above ten or twelve. A com- 
mon hen, if properly fed, will lay upwards of a 
hundred from the beginning of fpring to the lat- 
ter end of autumn. In general, however, it is ob- 
ferved, that the fmalleft and weakeft tribes are the 
moft prolific; while the ftrong and the rapacious 
are abridged by fterility. Thus, fuch kinds as 
are eafily deftroyed, are as eafily repaired ; and Na- 
ture, where ftie denies the power of refiftance, ge- 
nerally compenfates the defedt by beftowing ex- 
traordinary fertility. 
Birds in general, though naturally timid, are 
feldom frightened away from their ufual haunts; 
they are perfeftly formed for a wandering life, and 
fupplied with powers to fatisfy all their appetites. 
But, though they are fo well qualified for changing 
their retreats with eafe and rapidity, moft of them 
remain contented in thole diftrifts in which they 
have been bred, feldom exerting their powers in 
proportion to their endowments. The rook, if 
undifturbed, will never defert it's native grove ; the 
blackbirddoes not often relinquifti it's ufual haunts; 
and the red-breaft, though feemingly mild, claims 
a certain difbift, from whence it feldom moves, 
but drives from thence every intruder of it's own 
fpecies without pity or remorfe. 
Hunger, climate, and fear, are to Birds the chief 
incentives to migration; and from one or other 
of thefe powerful motives, thofe which are called 
Birds of paiTage annually forfake us for fome time, 
and afterwards make their regular and expefted 
returns. Though nothing, pefhaps, has excited the 
curiofity of mankind more than thefe annual mi- 
grations, few fubjefts continue fo much enveloped 
in uncertainty. The caufe of their retreat from 
fome gC our European iflands is generally fuppofed 
to originate either from a fcarcity of food at cer- 
tain feafons, the alterations of the climate, or the 
want of a fecure afylum from the perfecution of 
man during the time of incubation and foftering 
their young. Thus, in Sweden, at the approach 
of winter^ the ftariing, no longer finding fubfift- 
BIR 
ence in that klngdom3 defcends annually inro Ger- 
many; and the hen- chaffinches of the fame coun- 
try are obferved to fly through Holland in large 
flocks about the beginning of autumn, in order 
to pafs their winters in a milder climate. 
Some Birds are known to undertake journleSi 
the length and fatigues of which would intimidate 
human perfeverance. In fpring, the quails foi- 
fake the burning heats of Africa for the milder 
fun-beams of Europe ; and, after continuing with 
us during the fummer, wing their way back to en- 
joy the temperate air of Egypt, as foon as it be- 
gins to be delightful. Thefe peregrinations ap- 
pear to be concerted fome days previous to their 
departure : multitudes of them afiemble in Ibme 
open place; and, by a kind of chattering, feem 
to fettle the method of procedure. Their plan 
of operations being determined on, they all take 
flight together i and often appear hovering in fuch 
prodigious numbers over the fea, that to mariners 
they appear like a cloud refting on the horizon. 
The boldeft, ftrongeft, and by far the greateft num- 
ber, carry their plan into execution : but others of 
their company grow weary by the way ; and, quite 
exhaufted by the fatigues of irheir flight, drop into 
the fea, and fometimes even on the decks of 
fhips. 
Among the amazing number of water- fowl 
which frequent our coafts, it is curious to refled 
how few are known to breed on them. It is cer- 
tain, however, that they cannot quit this country 
merely for the want of food ; though to obtain a 
more fecure retreat oiay perhaps be their chief 
motive. This country is probably now too popu- 
lous_ for Birds fo ftiy and timid : wlien it was lefs 
cultivated, and contained extenfive trails of woods 
and marft^es, many fpecies of Birds which now mi- 
grate, remained with us throughout the year. The 
great heron and the crane, which have long for- 
faken this country, in former times bred familiarly 
in our marflies, feemed to animate our fens, and, 
like the generality of cloven-footed aquatic fowls, 
built their nefts on the ground. They had then but 
little to dread: the furrounding marflies proted- 
ed them from all carnivorous quadrupeds, and 
their own ftrength from Birds of prey; but, in 
proportion as agriculture increafed, they were more 
and more difturbed by the intrufions of man; and 
were at length obliged to feek odier retreats, wher? 
they might live miore remote from dangers and 
alarms. 
Though the tribes of the duck kind are very nu- 
merous, we know of no more than five which breed 
in this country; namely, the tame fwan, the tame 
goofe, the ftieldrake, the eider-duck, and the wild 
duck: the reft unite with that amazing quantity of 
v/ild fowl which inhabit the dreary lakes and de- 
farts of Lapland, where they perform, in undif- 
turbed fecurity, the duties of incubation and nutri- 
tion. There are, indeed, but few of this kind which 
cannot be traced to the northern defarts; and to 
countries abounding with lakes, rivers, fwam:ps, and 
mountains covered with thick and gloomy fbrefts, 
which affbrd the moft perfedfafety to thefe naturally 
timid animals : from the thicknefs and extent of 
the woods in thofe regions, the ground continues 
moift and penetrable during the fummer feafon j 
and the woodcock, fnipe, and other Birds with 
flender bills, can feed with convenience and eafe ; 
while thofe wliich are web-footed find plenty of 
food fronri the numbers of infeds which fwarm there 
in incredible numbers. It is not therefore afto- 
niftiing that amazing numbers of fowls Ihould de- 
fcend 
