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KIDD'S OWN JOURNAL. 



ground, and the upper portion of it, continu- 

 ing its progress, rushes over the lower, 

 dashing itself upon the beach in a torrent of 

 curling foam. Dr. Wollaston, on one occa- 

 sion, ascertained the velocity of the waves to 

 be at the rate of sixty miles an hour. 



Whilst on the shore our attention will be 

 drawn to the sea-gulls, which we behold, from 

 time to time, skimming over the sea, and 

 plunging their beaks into the wave to strike 

 their finnyprey. That birds are considerably 

 heavier than the element in which they fly, is 

 obvious ; what, then, can be the reason that 

 they are enabled to support themselves in so 

 light a medium ? The balloon and the soap- 

 bubble, we need hardly explain, rise in the 

 air because they are filled with an air still 

 lighter than themselves, which renders them 

 specifically lighter than the atmosphere ; but 

 this is not the case with birds ; for we see that 

 the moment the sportsman levels his piece at 

 the poor victim and it receives its shot, it 

 falls heavily to the ground — showing that its 

 floating capacity depended on a different prin- 

 ciple. 



The flight of birds appears more to re- 

 semble the flying of a kite, which we know 

 does not depend on its specific gravity, 

 because the paper and wood of which it is 

 formed are much heavier than air ; but the 

 theory of its remaining suspended depends 

 on the pressure of the wind on its under 

 side acting against the resistance of the 

 string by which it is held ; and the oblique 

 position in which it is balanced causes it 

 to ascend, and, as it were, to float in the 

 air. On the same principle, birds can only 

 remain suspended whilst they continue mov- 

 ing through the air ; and the motion of 

 their wings impelling them forward, has an 

 effect similar to the string of the kite ; for 

 it is the same thing whether we pass through 

 the air, or whether the air passes by us. On 

 a calm day, the boy cannot get his kite to as- 

 cend, unless he continue running with it ; 

 thus causing it to pass through the air ; but 

 on a windy day the kite will rise, though he 

 remain stationary. Whilst the bird, there- 

 fore, continues in motion, it floats in the air, 

 by the resistance of that fluid against the 

 breast and the under surface of its wings. 

 AVe may often watch a large bird, when de- 

 scending from a height, with wings out- 

 stretched, soaring along without any appa- 

 rent exertion. The momentum he has ac- 

 quired, assisted by the descending nature of 

 his flight, enables him to pass over a great 

 distance on this inclined plane before he 

 reaches the ground. If, instead of alight- 

 ing, he still continues his flight, it will be ob- 

 served, that as soon as he changes to a hori- 

 zontal direction, he is obliged to make use 

 of his wings to propel himself along. The 

 tail of the bird acts the same part as the 



rudder to a ship, for by it he directs his 

 course, and elevates or depresses his flight at 

 pleasure. 



From observing the feathered tribe, we 

 will now turn our attention to the dwellers 

 in the deep : and here we find that fishes 

 float according to their specific gravity ; and 

 are enabled to alter this gravity at pleasure, 

 by means of an air-vessel situated in their 

 bodies, which is surrounded by a strong mus- 

 cular fibre. When the fish wishes to de- 

 scend, he compresses this air vessel by means 

 of the muscle. This reduces the bulk of the 

 fish, and accordingly it sinks. When wish- 

 ing to ascend again, the fish relaxes the fibre, 

 the compressed air then immediately expands, 

 and the fish becomes specifically lighter, 

 and rises to the surface. When fishing 

 for cod where the water is very deep, it 

 is no uncommon circumstance for the fish 

 to be found with the air-bladder burst on 

 arriving to the surface of the water. This 

 arises, from the rapidity with which the fish 

 has been hauled up having removed the 

 pressure from the outside of the air-vessel, 

 before the membrane has had time to dilate 

 and expand itself; and, consequently, the 

 sudden expansion of the air within, when 

 the outer pressure is removed, causes the 

 vessel to burst, and destroys the fish. 



Surely nothing can be conceived more 

 beautifully arranged than this means which 

 the fish possesses of adapting itself to the 

 different densities of the water in which it 

 swims ; but every work of Nature is alike 

 replete with the same perfection, though 

 we discern but a very small portion of its 

 beauties. * 



* From " The Scientific Phenomena of Domes- 

 tic Life," a perusal of which we cannot recom- 

 mend too heartily. 



ENGLAND AND TURKEY,— 

 A CONTRAST. 



I send you, Mr. Editor, for insertion 

 in our OWN Journal, a little morceau which 

 I have translated from Theophile Gautier's 

 " Loin de Paris." There is " something" in 

 it, which your readers will readily appreciate. 



In Turkey, the beggar in rags takes his place 

 upon the divan of the cafe, next to the most 

 sumptuously-dressed Turk, without the latter 

 drawing back to avoid the contact of a greasy, 

 frayed-out garment, with his own magnificent gold- 

 embroidered costume. Still, certain classes have 

 their habitual places of meeting ; and the cafe 

 with a marble fountain, situated between Serai 

 Bournon and the mosque of Yeni Djarni, in one 

 of the finest quarters of Constantinople, is fre- 

 quented by the best society in the town. 



A charming and peculiarly Oriental feature, 

 lends to this cafe, in European eyes, the grace of 

 poetry. Swallows have attached their nests to 



