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Account of the Great Speckled Diver AS one of my neighbours was

or Loon. From Wsite's Naturals traversing Wolmer forest from ist's Calendar,

Bramshot aci oss the moors, he

found

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and the heat communicated is in every case proportional to the quantity of absorp-
tion. It appears, from some ingenious experiments of Mr. Bouguer, that we re-
ceive only four-fifths of the rays of a vertical sun; and when that lumiuary apo
proaches the horizon, the portion of this light, which reaches the surface of the
earth, is much smaller. Thus, at an elevation of 20 degrees, it is one-half ; at
that of 10 degrees, one-third; and at that of five degrees, one-eighth. Hence,
the sun-beams are most powerful on the summits of lofiy mountains, for they sufe
fer the greatest diminution in passing through the dense air of the lower regions.
If the air derived its heat from the surface of the earth, those countries would be
Warmest which enjoyed the greatest quantity of sun-shine. The Eritish islands are
shrouded in clouds nine months of the year; yet our climate is milder than that
of the same parallel on the continent, where the sky is generally serene. The ele
vated town of Quito, exposed to a brilliant sun, enjoys a temperate air; while
the Peruvian plains, shaded with fleecy clouds, are parched with heat. Were the
reasoning in the text to be admitted, we would conclude, that the tops of moun-
tains are warmer than their basis. 'To say that air, much rarified, is not suscepo,
tible of heat, is a very extraordinary assertion, since we are acquainted with no
substance whatever that may not be heated. Besides, a more istense cold may be
artificially produced than what prevails in the lofty regions of the atmosphere,
. We must recur to other principles for the true solution of the fact. It is indiffe-
rent whit portion of the air first receives the heat; the effect depends entirely on
the nature of its distribution. If the atinosphere were of an uniform dens ty
throughult, the heat would, at all heights, be likewise the same. But as the dena
sity varies according to the altitude, the distribution of heat is affected by that
circumstance, and follows a certain corresponding law. I would gladly develope the
principles from which this theory is deduced, bui the popular nature of the present
treat se forbids all abstract discussion. I shall, therefore, content myself with giving
a table of the diminution of heat at different altitudes.

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Altitude iu feet.

3,000 6,000 9,000 12,000 15,400 18,000 * 21,200

Diminution of heat, in degrees of

Fahrenheit.

120 241 S8 53 685 863

941

The diminution of heat, on the ascent, is not quite so great in extensive continents: for the intercourse between the rare and the dense portions of the atmosphere is, ia this case, necessarily slow, and the heal, which is principally formed at the surface, will only be partially dispersed.

It is a common mistake to suppose, that the same heat obtains, at a certain depth, in every part of the globe. The fact is, that heat, originally derived fron the sun, is communicaied very slowly to the matter below the surface, which, therefore, does not feel the vicissitude of seasons, but retains the average temperam ture of the climate for many ages. Hence the utility of examining the heat of springs which is the same with that of the substances through which they flow.

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HISTORY... found a large uncommon bird Aut. give strength and increase the tering in the heath, but not wound. power of swimming. The foot, ed, which he brought home alive. - when expanded, is not at right On examination it proved to be angles to the leg or body of the Colymbus glacialis, Linn.: the bird: but the exterior part inclingreat speckled diver or loon, which ing towards the head forms an a.

most excellently described in cuie angle with the body; the ina Willoughby's ornithology. tention being not to give motion

Every part and proportion of this in the line of the legs themselves, bird is so incomparably adapted to but by the combined impulse of its mode of life, that in no in.' borh in an intermediate line, the starce do we see the wisdom of line of the body. God in the creation to more ad. Most people know, that have vantage. The head is sharp, and observed at ail, that the swimming smaller than the part of the neck of birds is nothing more than a adjoining, in order that it may walking in the water, where one pierce the water; the wings are foot succeeds the other as on the placed forward, and out of the cen- land; yet no one, as far as I am ire of gravity, for a purpose which aware, has remarked that diving shall be noticed he:eatter; the thighs fowis, while under water, impel quite at the podex, in order to fa- and row themselves forward by a cilitate diving; and the legs are motion of ineir wings, as well as fat, and as sharp backwards al. by the impulse of their feet : but most as the edge of a knife, that such is really the case, as any perin striking they may easily cut the son may casily be convinced, who water ; while the feet are palmat. will observe ducks when hunted ed, and broad for swimming, yet by dogs in a cliar pond. Nor do so folded up when advanced for. I know that any one has given a ward to take a fresh stroke, as 10 reason why the wings of diving be full as varrow as the shank. fowls are placed so forward: doubt. The two exterior toes of the feet Jess, not for the purpose of

pro. are longest; the nails flat and moting their speed in flying, since broad resembling the human, which that position certainly impedes it; The following table exhibits the average heat of-places on the level of the sea, computed by the celebrated astronomer, professor Nieyer, for every five degrees of latitude. Latitude. Average Temperature.

Latitude.. Average Temperature. 834

494
82
804
78
745

355
71

3:31
67
625

92
45

58 By comparing this table with the preceding, it is easy to discover, for any titude, the altitude of the curve of congelation, or where the aver.ge temperature is 32°...-E. E.

but

840

3910

45

0 5 10 15 20 25 30 35

50
55
60
65
70
75
80
85
90

924

a

but probably for the increase of word Aambant (Aaming), because their motion under water, by the it appears, at a distance, like a use of four oans, instead of w; Aame of fire. He g nera:ly inha. yet were the wings and feet nearer bits in swanopy grour.ds, and salt together, as in Lond birds, they marshes, in the waters of which would, when in action, rather hin. he constructs his hest, by raising der than assist one another. out of tht moisture, of a foot deep,

This Coly mbus was of conside. a licele hillock of mud, a foot and rable bulk, weighing only three a half high. He makes a hole in drachms short of three pounds a. the : unmit of this lit le hi.lock; voirdupoise. It measured in length in this the hen deposits two eygs from the bill to the tail (which and hatches them, with her feet was very short), two fecimand:la: sunk in the water, by means of the the extremities of the coes-fout 'extreme length of her legs. When inches more ; and the breadth of several of these birds are sicing at the wings expanded was 4z'inches. the same tire on their eggs, in A person aitempted to eat ihe the midst of a swam;, you wouid body, but found ii very strong and take them, at a distance, for the rancid, as is the flesh of all birds flames of a confi gration, bursting living cu fish. Divers or loons, from the bosom of the warers. though bred in the most rontheriy Other fow's present contrasts of parts of Europe, yet are seen with us a different kind oa the same shores. in very severe winter. ; and on the The pelican, or wide tiroi, is a Thames are called 'prat loons, be. bird white and brown, provided cause they prey much on that sort of wiih a large bag under iis beak, fish.

which is of exci sive length. Out The legs of the Colymbi and he gres every morning to store his Mergi are placed so very back. bag with fish : a.d. ine supy of ward, and so our of all centre of the dy having been accomplished, gravity, that these birds cannot he perches on some pointed roc'ós walk at all. They are called hy Lin. on a level with the water, where natus compedes, because they move he ständs immoveable vill the even. on the ground as if shackled, or ing, says father Du Tertre*, " as fettered,

in a state of pre found sorrow, with

the head drooping, from the weight Conirists and C woans cies beizuren of his long bibig and eyes fixed on

Animals and the Earth. From Dr. the agirated ocean, as -motionless Hurter's Translution of St. Pierre's as a statue, of marble.", On the Siwai's wf Nature.

dusky strand of those seas may fre.

quently be distinguished herons THERE is seen, on the shores while as snow, and in the azure of India, a large and beautiful plains of the sky, the paillencu of a bird, white, ard fre.coloured, call. very whire, skimming through it ed the Ratinge, not that ji vis ofs almost out of sight : he is someFlemish extadion, abue the name tithes agirzed over wiih a bright is derived from the old French red, baving likewise the two long

6. Sant 7.40*
• History of the Antilles.

feather

a

feathers of his rail the colour of five; -of March last, I observed, by the as ihat of the South.seas.

brink of the rivulet which wasbes In many cases, the deeper that, the Gobelins", a buscerty of the the ground is, the more brilliant colour of brick, reposing with ex. are ihe colours in which the aniparded wings on a cuft of grass. ma', destined to live upon it, is On my approaching him, he flew arrayed. We have not, perhaps, off. He alighted, at some paces dis. in Europe, any insect with rich:s tance, on the ground, wh ch, at and gayer çiothing than the ster. that place, was of the same colour coraceous scarab, and the fly, which wish himself, I approached him bears the same epithet. This jast, a second time; he took a second is brighrer than burnished gold and digbe, and perch:d again on a steel; the other, of a hearispheri. similar stripe of earth. in a word, cal form, is of a fine blue, incin. I found it was not in my power ing to purple ; and in order to ren. to oblige him to alight on the der ihe contrast complere, he ex. grass, though I made frequent at. haies a strong and agreeable odour jempis to that affect, and though of musk.

the spaces of earth which separated Narure has bes:owed at once, in the ruriy.soil were nasrow, and few the colours of ionoxious animals, in number. contrasts with the ground on which This wonderful instinct is like. they livé, and consonances wish wine :conspicuously evident in the that which is:djacent, and has su- cameleon. : This species of lizard, peradied the instinct of employing whose motion is extremely slow, these alternately, according as ycod is indemnified for this, by the in. orʻbad fortune prompts. . These comprehensible faculty of assumwonderful accommodations may be ing, at pleasure, the colour of the temarked in most: of our small ground over which : he, moves. birds, whose flight is feeble,' and With this advantage, he is ena. of short duration. The grey lark bled to elude, the eye of his pur. finds her subsistence among the suer, whose speed would soon have grass of the plains ? Does any thing overtaken him. This faculty is.in terrify her, she glides away, and bis will, for his skin is by no means takes her station between two little a mirror, It reflects only the clods of earth, where she becoides colour of objects, and not their invisible. On this post she .se. form. What is farther singularly ma'ns in such perfect tranquillisy, remarkable in this, and perfectly as hardly to quit it, when the foot, ascertained by naturalists, though of the fowler is ready to crush her. they assign no reason tos it, he can

The same thing is true of the par. assume all colours, as brown,.grey, tridge. I have no doube that these yellow, and especially green, which defenceless birds have a serse of is his favourite colour, but never • those contrasts and corresponden. red. The cauneleon has been plac. cies of colour ; for I have semark. ed, for a weeks together, amidst : ed it even in insects. In the mond scarlet stuffs, without acquiring the • A small village in the maburbier Paris, noted for ice

in fine the pestry and superb mirrors

slightest

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nature

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slightest shade of that colour. Na. part of resinous trees, which shelter ture seems to have withheld froin min froin ihe snows by the closethe creature this shining hue; be. ness of their foliage, and which cause it could serve only to ren. furnish him, during the winter der him perceptible as a greater season, with torches, and fuel for distance ; and farthes, because this his fire-side. It is very remark. colour is that of the ground of no able, that the leaves of ihase ere species of earth, or of vegetable,' green trees are filiform, and are on which he is designed to pass his extremely adapted, by this confi. life.

guration, which possesses the farBut, in the age of weakness and ther advantage of reverberating the inexperience,

coafounds heat, like the hair of animals, for the colour of the harmless animals, resistance to the impetuosity of the with that of the ground on which winds, that beat with peculiarvio. they inhabit, without committing lence on elevated situations. The to them the power of choice. The Swedish naturalists have observed,

pigeons, and of most that the fastest pines are to be granivorous towls, are clo:bed with found on the dryesi and mast sanly a greenish shags coat, resembling regions of Norway. The larci, the mosses of the nesis. Cater. which takes cqual pleasure in the pillars are blind, and have the cold mountains, has a very resi. complexion of the foliage, and of nous trunk. the barks, which they devour. Mathiola, in his useful commen. Nay, the young fruits, before they tary on Dioscorides, informs us, come to be armed with prickles, that there is no su'istance more pro. or inclosed in cases, in bitter pulps, per than the charc al of these crees, in hard shells, !o protect their for promptly melting the iron mi. seeds; are, during the season of their perals, in the vicinity of which expansion, green as the leaves they peculiariy thrive,' They are, which susroard them. Some em. besides, loaded with mosses, some bryons, it is true, such as those of species of which catch fire from cettajn pears, are ruddy or brown; the slightest spark, He relates, but they are then of the colour of that being obliged, on a certain the bark of the tree to which they occasion, to pass the night in the belong. When those fruits have in. lofty mountains of the strait of closed their seeds in kernels, or nuts, Trento, where he was botanizing. so as to be in no farther danger, they he found there a great quantity of then change colour. They become larches (larix ) bearded all over, lo yellow, blue, gold-coloured, red, use his own expression, and com, D'ack, and give to their respective pletely whitened with moss. The Trees their natural contrasts. It shepherds of the place, willing in is strikingly remarkable, that every amuse him, set fire to the mossos fruit which has changed colour has of some of these trees, which was seed in a state of maturity. immediately communicated with

It is in the countries of the the rapidity of gunpowder touched North, and on the summit of cold with a match. Amidst the ob mountains, that the pirë grows; scũrity of the night, the fame and and the fir, and the cedar, and most the sparks scem to ascend up to

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