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water; but if he stoops down and lays his eye near the furface, he will find that the boat is covered by the convexity of the water. Several navigators have failed round the earth; not in an exact circle, the winding of the fhores preventing them from failing on in a direct courfe; but by failing continually to the weftward, they have reached the place from whence they at first departed. This was performed by Magellan, Cavendish, Sir Fran cis Drake, Lord Anfon, Bougainville, Com modore Byron, the captains Carteret, Wallis, Cook, and others. All the appearances of the heavens, both at land and fea, are the fame as they would be were the earth a globe, which proves that it really is fuch, and, laftly, eclipfes of the moon, which are caused by the fhadow of the earth falling on that planet, demonftrate that the earth is of a globular figure; for this fhadow is always globular, whatever fituation the earth may be in at that time now a body must be globular which always cafts a circular fhadow. Nor are the little unevenneffes on the earth's surface,

arifing from hills and valleys, any material objection to its being confidered as a round body; because the highest mountains bear a lefs proportion to the bulk of the earth, than the little rifings on the coat of an orange bear to that fruit; or a grain of fand to an artificial globe of nine inches diameter: and accordingly, we find that the mountains and vallies on the furface of the earth, caufe no irregularities in the fhadow during a lunar eclipfe; the circumference thereof being even and regular, and appearing as if caft by a body truly regu lar,

The methods made ufe of to meafure the earth are very plain and easy to be understood. But it will be neceffary to obferve that every great circle, and confequently the circumference of the earth, is divided into 360 equal parts, called degrees, and every degree into 60 equal parts, called minutes, &c. It was neceffary to give the preference to fome number, and, probably, that of 360 was fixed upon for this reafon, that it admits of feveral convenient divifions, as well by the figure 2 Rs 3. Thus the half is 180, the quarter 90,

and the half quarter 45. Alfo the third of 360 is 120, the third of which again is 40. Few other numbers can boaft of this advantage, especially as every number in both the above divifions is alfo further divifible by five

As every circle is divided into 360 degrees, if at two places, fituated north and fouth of each other, the altitude of the fun be taken oa the fame day at noon, and the fun be found to be one degree nearer to the zenith at one place than the other, those two places are one degree afunder, Now if the distance between these two places be measured by a chain, or otherwife, we fhall know the length of a degree and confequently of any part of a degree, in English meafure. This has been done by feveral geographers, particularly by Richard Norwood, who, in the year 1635, obferved the difference of latitude, and meafu red the distance between London and York, by, which it appeared, that 367,200 English feet, or 69 miles and a half, and 14 poles, make a degree. Hence the whole circumference of the globe will be 25,020, and its diameter 7:970 English miles, reckoning 69 and a half

to a degree. If the odd poles be taken into the account, the circumference will then be 25,035 miles, and 240 poles.

The map better idea of the world itself, than the best verbal description. It reprefents the artificial globe taken out of its horizon, fqueezed fiat, cut through, and the two hemifpheres placed clofe to each other.

of the world will give you a much

Into how many parts is the earth divided? Into four parts or quarters; viz. 1. Europe; 2. Afia; 3. Africa, aud 4. America.

What are the other nominal parts of the earth; or how is it yet further divided, in relation to land and water?

It is divided into ten different parts; five belonging to land; viz. 1. Continent; 2. An island; 3. A promontory or cape; 4. A peninfula. 5. An iftius. The other five belonging to water; viz. 1. An ocean; 2. A lake; 3. A bay; 4. A gulf; and 5. A ftrait. The fe answer to each other, as more plainly appears by the following defcription:

LAND.

1. A continent is a large tract or vast ex

tent of main land, not separated by any ocean. Thus Europe, Afia, Africa, &c. are conti

nents.

2. An island is a tract of land furrounded with water; as Great Britain, Ireland, Ja maica, Madagascar, &c. &c.

3. A promontory or cape, is a portion of land running far into the fea; as Cape Verde, Cape of Good Hope, &c. &c:

4. A peninfula is a part or portion of the earth almost furrounded with water, fave only a part or narrow neck of land, which joins or unites it to a continent; as Jutland, the Morea, the Crim Tartary, &c.

5. An iftmus is a narrow part of land, by which a peninfula is joined to a continent of main land, as the iftmus of Panama, which joins North and South America together; the iftmus of Corinth, &c. &c..

WATER.

An ocean, or fea, is a large extent of collection of waters not divided by land; such as the Atlantic or Western Ocean, the Indian Ocean, &c.

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