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edges of the machine from being entangled by any ragged prominences of rock. His machine is of wood, suspended by ropes, and having a leaden weight appended to it, by means of which the mouth of the bell is kept always parallel to the surface of the water, whether the machine, taken altogether, is lighter or heavier than an equal bulk of water. By these weights alone, however, the bell would not sink; another is therefore added, which can be lowered or raised at pleasure, by means of a rope passing over a pully, and fastened to one of the sides of the bell. As the bell descends, this weight, called by Mr. Spalding the balance weight, hangs down a considerable way below the mouth of the bell. In case the edge of the bell is caught by any obstacle, the balance weight is immediately lowered down, so that it may rest upon the bottom. By this means the bell is lightened, so that all danger of oversetting is removed; for being lighter, without the balance weight than an equal bulk of water, it is evident that the bell will rise as far as the length of the rope affixed to the balance weight will allow it. This weight, therefore, serves as a kind of anchor to keep the bell at any particular depth which the divers may think necessary; or, by pulling it quite up, the descent may be continued to the very bottom. By another very ingenious contrivance, Mr. Spalding has rendered it possible for the divers to raise the bell, with all the weight appending to it, even to the surface of the water, or to stop it at any particular depth, as they think

proper; and thus they would still be safe, even though the rope designed for pulling up the bell should be broken. For this purpose the bell is divided into two cavities, both made as tight as possible. Just above the second bottom are small slits in the sides of the bell, through which the water, entering as the bell descends, displaces the air originally contained in its cavity, which flies out at the upper orifice of a cock expressly fitted for that purpose. When this is done, the divers turn the handle which stops the cock; so that if any more air were to get into the cavity, it could no longer be discharged through the orifice as before. If, therefore, the divers wish to raise themselves, they turn the cock, by which a communication is made between the upper and under cavities of the bell. The consequence is, that a quantity of air immediately enters the upper cavity, and forces out a quantity of the water contained in it, and thus renders the bell lighter by the whole weight of the water which is displaced; thus, if certain quantity of air is admitted into the upper cavity, the bell will descend very slowly; if a greater quantity, it will neither ascend nor descend, but remain stationary; and if a larger quantity of air be still admitted, it will rise to the top. It should be observed, however, that the air which is thus let out into the upper cavity, must immediately be replaced from the air-barrel; and the air is to be let out very slowly, or the bell will rise to the top with so great a velocity, that the divers will be in danger of being shaken out of their

seats. But by following these directions, every possible accident may be prevented, and persons may descend to a very great depth without the smallest apprehension of danger. The bell also becomes so easily managed in the water, that it may be conducted from one place to another, by a small boat, with the greatest ease and with perfect safety to those within.

CYCLOPEDIA

LESSON IV.

THE NORTH CAPE.

Terminated vicinity existence picturesque chequered temperate immoveable horizon

particular spectacle phenomenon inhabitants tremendous extraordinary January

ascertained perpetual December This cape, forming the most northerly point of the continent of Europe, may be regarded as one of the sublimest wonders of nature. It is situated within the arctic circle, in seventy-one degrees ten minutes north latitude. A late traveller states, that a little before midnight, its rocks appeared to be nearly of an equal height, until they terminated in a perpendicular peak; but on a closer view, those within were found to be much higher than those of the extreme peak, or point.

Their gene

ral appearance was highly picturesque. The sea broke against this immoveable rampart, which had withstood its fury from the remotest ages, and formed a thick border of white froth. This grand spectacle was illuminated by the sun, and the shade which covered the western side of the rocks, rendered their aspect still more tremendous. The height of these rocks could not be ascertained; but everything was on so grand a scale, that a point of comparison could not be afforded by any ordinary known objects.

On landing, the party discovered a grotto, formed of rocks, with a surface washed smooth by the waves, and having within a spring of fresh water. The only accessible spot in the vicinity, was a large hill, surrounded by enormous crags. From the summit of this hill, turning towards the sea, they perceived to the right a prodigious mountain, attached to the cape, and rearing its sterile mass to the skies. To the left, a neck of land, covered with less elevated rocks, against which the surges dashed with great violence, closed the bay, and admitted but a contracted view of the ocean. order to see as far as possible into the interior, our traveller climbed nearly to the summit of the mountain, where a most singular landscape presented itself to the view. A lake in the foreground had an elevation of at least ninety feet above the level of the sea; and on the top of an adjacent, but less lofty mountain, was another lake. The view was closed by peaked rocks, chequered by several patches of snow. At midnight the sun

In

Y

still remained many degrees above the horizon, and continued to ascend higher and higher until noon, when having again descended, it passed the north, without dipping below the horizon. This phenomenon, which is equally as extraordinary to the inhabitants of the torrid and temperate zones, as snow is to those who inhabit the torrid zone, could not be viewed without a particular interest. Two months of perpetual day-light, during the whole of which time the sun never sets, seem to place the traveller in a new state of existence, while its effect on the inhabitants of these regions is striking. During the time the sun is perpetually above the horizon, they rise at ten o'clock in the morning, dine at five or six o'clock in the evening, and go to bed at one. But throughout the winter season, from the beginning of December, until the end of January, when the sun never rises, they sleep more than half of the twenty-four hours, and spend the other half in sitting over the fire, all business being at an end, and constant darkness prevailing

LESSON V.

SONG OF THE CAPTIVE LARK.

'Tis merry morn

-the sun hath shed
His light upon the mountain head.
The golden dews are sparkling now
On heath and hill, on flower and bough;

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