brazen meridian, may be made to represent the meridian of any place. It is divided into four parts, of 90o each *. On one semicircle the degrees are numbered from the equator towards the poles; on the other from the poles to the equator. The former is used in finding the latitude of places, the latter in elevating the globe.

7. Latitude is the distance of any place, north or south, from the equator.

The latitude of a place can never exceed 90o, that being the distance of the poles from the equator. It is reckoned by degrees and minutes on the brass meridian, but in maps at the sides.

8. The longitude of a place is the distance of the meridian of that place, east or west, from the first meridian.

On globes it is reckoned on the equator; but in maps, at the top or bottom. Geographers in different countries have fixed upon different places for the first meridian. The Dutch have fixed upon the Peak of Teneriffe ; and the French on the island of Ferro, one of the Canaries. The English reckon from the meridian of Greenwich. The greatest longitude any place can have is 180°, or half the circumference of the globe.

9. Parallels of latitude are circles drawn parallel to the equator.

The circles on the globe drawn to represent the parallels of latitude become smaller the further they are distant from the equator; that representing the parallel of 60o, is only half the size of the equator. In all maps they are the lines drawn from one side to the other.

SECTION I.

PROBLEM I.

To find the Latitude and Longitude of any place.

BY THE GLOBE.-Bring the given place to the brass meridian; then the degree of the meridian directly over it shows the latitude, and the degree of the equator under the meridian shows the longitude.

BY MAPS.-Ascertain with a pair of compasses the dis

Every circle is, by geometers, divided into 360 degrees.

tance from then earest parallel and meridian when these are not drawn through the place, and at one side and at the top or bottom of the map the degree of latitude and longitude will be found.

To distinguish East from West Longitude.

RULE.—If the figures increase towards the right hand, the longitude is east; if towards the left, it is west.

EXAMPLES.

1. Required the latitude and longitude of Edinburgh.

Bring Edinburgh below the meridian, we find, over it nearly, the 56th degree of North latitude, (55° 58′,) and the point where the meridian cuts the equator is nearly 34 (3° 12′) degrees west of London.

Required the latitude and longitude of the following capital cities of Europe.

50 Hanover

51 Dresden

52 Munich

53 Magdeburgh

54 Olmutz

55 Stralsund

When the longitude is taken from Ferro Island, it may be reduced to the meridian of London by the following

RULE. If the longitude be east, 17° 45′ must be subtracted; if it be west, the same number must be added; and the sum or difference will be the longitude from the meridian of London.

If the place lie between the meridians of Ferro and London, subtract the longitude east from Ferro, from 17° 45'; and the remainder will be the longitude west from London.

N. B. The above rule reversed will reduce the longitude from London to that from Ferro Island.

Ex. 1. The Cape of Good Hope has 36° 9′ E. L. from the meridian of Ferro,―required the longitude from London? Answ. 18° 24′ E. L. from London.

2. Gibraltar has 12° 23′ E. L. from Ferro,-what is its longitude from London? Ans. 5° 22′ W. L. from London.

3. Cape Horn has 49° 40′ W. L. from Ferro,-required its longitude from London?

4. Cape Comorin has 78° 5′ E. L. from London,-required the longitude from Ferro?

PROBLEM II.

Having the Latitude and Longitude given, to find the place.

BY THE GLOBE.-Bring the given longitude to the brass meridian; then, under the given latitude marked on the brass meridian, is the place sought.

BY MAPS.-The latitude and longitude being found at the sides and ends of the Map, imaginary lines may, with the aid of a pair of compasses and ruler, be extended from these points, which will meet at the place required.

EXAMPLES.

1. What place is situated in 48° 23′ N. L. and 4° 39′ W. L. from London? Answ. Brest in France.

Required the names of the places situated in Africa, whose latitudes and longitudes are as follow.

To find the Difference of Latitude between two places. If the latitudes are of the same name, subtract the less from the greater; if of contrary names, add them together.

In doing this and the next problem, either globes, maps, or tables of latitude and longitude, may be used.

When the two places are in opposite hemispheres, their latitudes being reckoned different ways, their sum must be taken; but when they are in the same hemisphere, their latitudes being reckoned the same way, their difference only must be taken.

EXAMPLES.

1. What is the difference of latitude between North Cape and C. Matapan in Europe? Ans. 34° 40'.

2. Between Tunis and C. of Good Hope? Ans. 71° 16′. 3. The middle of Nova Zembla and C. Comorin? 4. The mouth of Copper-Mine R. and Acapulco. 5. Between Cape Vela and Cape Horn, in S. America? 6. The south Cape of N. Holland and Torres Straits? 7. Between Cape Wrath and the Lizard Point? 8. Dunkirk and Perpignan? 9. Madrid and Mexico? 10. Between London and Botany Bay?

11. St. Jago, one of the Cape Verd Is., and St. Helena? 12. The Cape of Good Hope and Cape Comorin? 13. Calcutta and Batavia? 14. Manilla and Canton? What is the difference of latitude between the following sea-ports in Europe?