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67 



the dread of imminent danger, desire for 

 society, or longing for his mate, love, melan- 

 choly, &c., are expressed by a variety of 

 notes, which make a language intelligible 

 not only to birda of the same species, but 

 often to the other tribes. 



With respect to the feathers of birds, it 

 lias been truly said, that every form which 

 the most sportive fancy could create out of 

 the feathery material, and every hue that 

 the wannest imagination could picture to 

 itself, will be found among them. As a 

 general rule, the plumage of the cock bird 

 far exceeds in brilliancy that of the hen ; 

 and in many species a striking difference is 

 observable between their plumage in summer 

 and in winter ; but in most birds two changes 

 are observable ; namely, that in the spring, 

 which indicates the approach of the breeding 

 season, when the bird obtains a certain por- 

 tion of new feathers without losing any of 

 the old ones ; and in autumn, which is the 

 moulting season, when the old feathers are 

 thrown off, and new ones are produced in 

 their places. 



Birds may be distinguished, like quadru- 

 peds, into two kinds or classes granivorous 

 and carnivorous ; like quadrupeds too, there 

 are some that hold a middle nature, and par- 

 take of both. Granivorous birds are fur- 

 nished with larger intestines, and propor- 

 tionally longer, than those of the carnivorous 

 kind. Their food, which consists of grain of 

 various sorts, is conveyed whole and entire 

 into the first stomach or craw, where it 

 undergoes a partial dilution by a liquor se- 

 creted from the glands and spread over its 

 surface ; it is then received into another spe- 

 cies of stomach, where it is further diluted ; 

 after which it is transmitted into the gizzard 

 or true stomach, consisting of two very 

 strong muscles, covered externally with a 

 tendinous substance, and lined with a thick 

 ! membrane of prodigious power and strength: 

 in this place the food is completely triturated 

 and rendered lit for the operation of the gas- 

 tric juices. The extraordinary powers of 

 the gizzard in comminuting the food, so as 

 to prepare it for digestion, would exceed all 

 credibility, were they not supported by in- 

 controvertible facts founded upon experi- 

 ments. In order to ascertain the strength 

 of these stomachs, the ingenious Spalanzanl 

 made the following among many other cu- 

 rious and interesting experiments : lie 

 fixed twelve small lancets, very sharp, in a 

 ball of lead, which was forced down the 

 throat of a turkey-cock, and left eight hours 

 in the stomach ; at the expiration of which 

 the organ was opened, but nothing appeared 

 except the naked ball, the twelve lancets 

 having been broken to pieces, the stomach 

 remaining perfectly sound and entire. We 

 may observe also, that stones taken into the 

 stomach of birds are seldom known to pass 

 with the fasces, but being ground down and 

 separated by the powerful action of the 

 gizzard, are mixed with the food, and, no 

 doubt, contribute essentially to the health 

 of the animal. 



Carnivorous Birds are distinguished by 

 those endowments and powers with which, 

 they are furnished by nature for the purpose 



of procuring their food : they are provided 

 with wings of great length, the muscles which 

 move them being proportionally large and 

 strong, whereby they are enabled to keep 

 long upon the wing in search of their prey : 

 they are armed with strong hooked bills, and 

 sharp and formidable claws ; they have also 

 large heads, short necks, strong and brawny 

 thighs, and a sight so acute and piercing, as 

 to enable them to view their prey from the 

 greatest heights in the air, upon which they 

 dart with inconceivable swiftness and unde- 

 viating aim. The analogy between the 

 structure of rapacious birds and carnivorous 

 quadrupeds is obvious ; both of them are 

 provided with weapons which indicate de- 

 struction and rapine ; their manners are 

 fierce and unsocial ; and they seldom live 

 together in flocks, like the inoffensive grani- 

 vorous tribes. When not on the wing, rapa- 

 cious birds retire to the tops of sequestered 

 rocks, or to the depths of extensive forests, 

 where they conceal themselves in sullen and 

 gloomy solitude. 



Without the means of conveying them- 

 selves with great swiftness from one place to 

 another, birds could not easily subsist ; the 

 food which Nature has so bountifully pro- 

 vided for them is so irregularly distributed, 

 that they are obliged to take long journeys 

 to distant parts in order to gain the necessary 

 supplies : at one time it is given in great 

 abundance ; at another it is administered 

 with a very sparing hand ; aiid this is one 

 cause of those migrations so peculiar to the 

 feathered tribes ; the other chief causes are, 

 the want of a proper temperature of air, and 

 a convenient situation for the great work of 

 breeding and rearing their young. Such 

 birds as migrate to great distances are alone 

 denominated "birds of passage ;" but most 

 birds are, in some measure, birds of passage, 

 although they do not migrate to places very 

 remote from their former habitations. At 

 particular times of the year most birds re- 

 move from one country to another, or from 

 the more inland districts towards the shores: 

 the times of these migrations or Sittings are 

 observed with astonishing order and punctu- 

 ality ; but the secrecy of their departure, 

 and the suddenness of their re-appearance, 

 have involved the subject of migration in 

 general in great difficulty. Much of this 

 difficulty arises from our not being able to 

 account for their means of subsistence during 

 the long nights of many of those birds which 

 are obliged to cross immense tracts of water 

 before they arrrive at the places of their 

 destination : accustomed to measure distance 

 by the speed of those animals with which 

 we are well acquainted, we are apt to over- 

 look the superior velocity with which birds 

 are carried forward in the air, and the ease 

 with which they continue their exertions 

 for a much longer time than can be done by 

 the strongest quadruped. On this part of 

 the subject we have had occasion to make 

 more particular observations, when speaking 

 of the habits of certain migratory birds ; we 

 shall therefore merely add, from Bewick, 

 that from the advantage they possess in 

 being raised to considerable heights in the 

 air, they are enabled, with a sagacity pecu- 



