Sivut kuvina
PDF
ePub

Day falls minth of the Hours the Day the Hour the Opfe Hours be?

[ocr errors]

Western Side of the Horizon, and the Number of Hours between the upper Figure of 12, and the Hour the Index points to, thew how many Hours the Day is long, and consequentJy the Length of the Night; because so many Hours as the Day falls thort of 24, must be the Length of the Night; as when the Day is 16 Hours long, the Night must of course be 8 Hours long.

S. How shall I find those Places on the Globe where the Sun is in the Meridian at any time?

M. The Globe being rectified, and the Place where you are brought to the brazen Meridian, To find in

wbat Places set the Index of the horary Circle at the Hour of

the Sun is in the Day at that Płace, then tulh the Globe till ibe Me idian. the Index points to the upper 12, and you will see all those Places where the Sun is in the Meridian ; as for Example, if it be it in the Morning at London, and you set the Index at 11, turn the Globe till the Index points at the upper 12, and you will find Naples, which is an Hour or 15 Degrees East of London. And in all Places under the same Meridian ac Naples is, it must consequently be 12 at Noon at that Time.

In like manner, if it be 4 in the Afternoon at London, and you set the Index at 4, and turn the Globe till the Index points at the upper 12, you will find Barbadoes, which is four Hours or 60 Degrees West of London, and at all Places under the same Meridian as Barbadoes is, it must consequently be 12 at Noon at that Time.

S. How shall I discover where the Sun is vertical at any time of the Year?

M. The Sun can only be vertical in Guch Places as lie between the Tropics; and to know this, To find where you are only to find what Place the Sun is in the

vertical. Ecliptic, and bringing that Place to the brazen Meridian, observe what Degree of Latitude it has, for in all Places in that Latitude the Sun will be vertical that Day, and you will find all those Places only by turning the Globe round, and observing them as they come to the brazen Meridian.

S. How may I find where the Sun is above the Horizon, or shines without setting all the 24 Hours in the Northern Hemisphere?

M. The Day given must be when the Sun is in the Northern Signs, and having found the Sun's To find wbere

the Days are Place in the Ecliptic, you must bring that Place

24 Hours long to the brazen Meridian, then count the same Number of Degrees from the North Pole towards the Equa

P 3

tor

[ocr errors]
[ocr errors]
[ocr errors]

rbe Senis

tor, as there is between the Equator and the Sun's Place in the Ecliptic, then turn the Globe round, and in all the Places paffing under the last Degree counted from the North Pole, the Sun begins to shine constantly without setting on the given Day: And the Rule will serve vice versa for any Place let in the Southern Hemisphere, when the Sun is in the Southern Signs.

$. How do we discover the Length of the longest and shortest Days and Nights at any Place in our Northern Hemisphere?

M. Rectify the Globe according to the LaTo find tbe titude of the given Place, or which is the same Lengib of be

thing, bring the given Place to the Zenith, then any Place bring the first Degree of Cancer to the East Side

of the Horizon, and setting the Index of the Hour Circle to the upper Figure of 12, turn the Globe till the Sign of Cancer touch the West Side of the Horizon, and observe the Number of Hours between the upper Figure of 12, and the Hour the Index points to, and that is the Length of the longest Day, and the thortest Night consequently consists of so many Hours as the Day falls short of 24; and as for the Length of the Days and Nights in Southern Latitude, they are jult the reverse of those in Northern Latitude, and the Table of the Climates shews both the one and the other.

S. How may I find in what Places the Sun is rising or setting, or in its Meridian: Or what Parts of the Earth are enlightened at any particular time?

M, First find where the Sun is vertical at the To find a bere the Sun is ris given Hour, and bring that Place to the Zenith, fing, Jerring, under the brazen Meridian ; then observe what or in .be Me. Places are in the Eastern Semi-circle of the Horidian,

rizon, for there the Sun is setting, and in thofe Places in the Western Semi-circle of the Horizon the Sun is rising, and in all Places under the brazen Meridian it is Noon Day: All those Places in the upper Hemisphere of the Globe are enlightened, and those in the lower Hemisphere are in Darkness.

S. How shall I find the Distance of one place from another upon the Globe ?

M. If both Places lie under the fame Meridian, bring them to the brazen Meridian, and count thereon how many Degrees of Latitude the two Places are from each other, which being reduc'd to Units is the true Distance. Every Degree of Latitude containing 60 Geographical Miles, as has been obferv'd already; and R60 Geographical Miles make near 70

Englijh

millaces in the Fizon, fore in the Earth

20;

[ocr errors]

GEOGRAPHY, &c. 201 English Miles. If the two Places lie under the same Parallel of Latitude, then observe on the Equator how many Degrees of Longitude they are asunder, and observe in the Table A, how many Miles a Degree of Longitude makes in that Lati: tude, and then numbering the Degrees of Longitude on the Equator, reduce them to Miles, and that will give the Diftance of the two Places. For Instance, suppole Rotterdam lies in 52 Degrees of North Latitude, and 4 Degrees of Ealtern Longitude and Pyrmont lies under the same Parallel 5 Degrees East of Rotterdam, and I find that every Degree of Longitude in this Latitude makes 37 Miles, then I multiply 37 by 5, which makes 185, being the Number of Miles between Rotterdam and Pyrmont.

Where the two Places differ both in Longitude and Latitude, the Distance may be found by measuring the Number of Degrees they are ásunder by the Quadrant of Altitude, and reducing those Degrees to Miles. For Example, if I find the two Places are the Length of 10 Degrees afunder by the Quadrant, they must necessarily be 600 Miles distant from each other; because 60 Miles which is the Extent of I Degree of Latitude, multiplied by 10, makes 600 ·Miles on the Globe, in whatever Direction one Place lies from another, as the North, East, South, Weft, &c. .

S. How may I find how one place bears of another, that: is, whether it lies North-East, South-West, or on any other Point of the Compass from another Place?

M. Bring one of the Places to the Zenith, and fix the Quadrant of Altitude there, then extend

Te find bere

ore Place bears it to the other Place whose bearing you would of another. know, and the lower part of the Quadrant will intersect the wooden Horizon at the Point of the Compass inscrib'd on the wooden Horizon, which is the true Bearing of the given Place.

S. How shall I find on what Point of the Compass the Sun rises or sets at any Place?

M. Bring the given Place to the Zenith, and having found the Sun's Place in the Ecliptic, what Point bring the same to the Eastern Side of the Horizon, of the Comand it will thew on what Point of the Compass Point

ē pass obe Sun the Sun rises. On the other hand, if you bring the Sun's Place in the Ecliptic to the West Side of the Ho. rizon, it will thew on what Point of the Compass the Sun,

[ocr errors]

fets.

[ocr errors][ocr errors]

Of the grand Divisions and Subdivisions of the Earth.

S. Please to describe the Situation of the several Nations on the Face of the Earth.

M. The Earth is usually divided into the '2 Continents.

e Eastern and Western Continents, or into the old and new World. That on the right Hand in a Map of the World is ftiled the Eastern Continent, and that on the left, the Western Continent.

S. What does the Eastern Continent contain ? Eastern

M. The Eastern Continent comprehends EuContinent. rope, Asia, and Africa: Europe is the North

West Division, Afia the North-East Division, and Africa the South Division of this Eastern Continent.

The Division of the Habitable Earth, the square Miles

of each Division and Subdivision, Capital Cities, with the Distance and Bearing of each from London, also the Time of each Country compared with that of England.

THE Terraqueous Globe is divided into,

1. Europe

2,749,3497 II. Afia

10,257,487 III. Africa

8,506,208 IV. America

9,553,762 | Square Miles, bo

o Miles in Length, Habitable Earth

30,666,806 | to a Degree. Seas, and unknown Parts 117,843,821 Superficies of the whole Globe 148,510,627).

Division

| Distance Difference Division and Sub- Square

Capital Cities. division, Miles.

and Bear-lof Time ing from from Lond.

London.

prom Lond.

[ocr errors]

I. EUROPE.

*H.M. 1. Spain 150,243 Madrid

690 S 0 16 W 2. Portugal 27,851 | Lisbon

840 SW 0 38 W 3. France 138,837 Paris

203 E o 9 4. Italy 75,576 Rome

780 SE lo 5. Germany 181,631 Vienna 650 E 6. Holland

9,540 Amslerdam 132 E 7. Denmark 163,001 Copenhagen

480 NEO 50 E 8. Sweden 228,715 Stockholm 220 NEI 10 E 9. Rullia

1,103,485 Petersburg 1080 Nez 2 Ē 10. Poland

226,414 Warsaw 766 SE 1 23 E 11. Turkey in Eur. 212,240 Conftantinople 1300 SE II 56 E 12. British Isles 105,634 London

First Meridian. II. ASIA. 1. Turkey in Afial 510,717 | Bursa 1396 SE | 58 E 2. Arabia 700,000| Mecca 2640 SE 3. Perfia | 800,000 Ispahan 12550 E

13 21 E 4. India 1,857,500 Agra

3780 E 15 15 E 5. China

1,105,000 Pekin 4380 NE 6. Afiatic Illes 811,980 7. Tartary 1. Chinese

644,000 Chinyan 14480 NE 2. Independent) 778,290 Samarchand 12800 E 26 E

3. Muscovite 13,050,000 Tobol.ky 2412 NE 4 10 E III. AFRICA. 1. Egypt 140,700 Grand Cairo 1920 SE 2 10 E 2. Barca 166,400 Folemeta 11440 SE ( 26 E 3. Abex

30,000 Erquiko 3580 SE 2 36 E 4. Fez & Morocco 118,800 Fez & Morocco

US 1080 So 217,

1l 1290 S 10 30 5. Taflet and Se- 100,600 Tafiet and Se- 1376 Slo 30 gelmesse

gelmele 11240 S 18 6. Algier 143,600 Algier

920 S 1213 E 7. Tunis 54,400) Tunis

| 990 SE JO 39 E

[ocr errors]
[ocr errors]

* A Degree of Longitude being 4 Minutes in Time, therefore by having the Longitude we have the Time. A Watch that is set to Time at London would be 16 Minutes too fast at Madrid, as it lies to the West of the Meridian of London : And Vienna being 16 Degrees and 20 Minutes to the East of the Meridian of London, consequently a Watch set at London would be 1 Hour and 5 Minutes too flow at Vienna,

Division

« EdellinenJatka »