Note Thofe parts of the Ocean, which border upon the land, are called by various names, according to thofe of the adjacent countries; as the British Sea, the Irish Sea, the French and Spanish Sea.

16. A Lake is a collection of standing water, furrounded by land, and having no communication by fea; as the Lake of Geneva, the Lake of Aral, and the Cafpian Sea, which is properly a Lake.

17. A Gulf is a part of the sea, almost encompaffed with land, or that which runs up a great way into the land; as the Gulf of Venice, &c. but if it be very large, it is rather called an Inland Sea; as the Baltic Sea, the Mediterranean Sea, the Red Sea, or the Arabian Gulf, &c. And a small part of the fea, thus environed with land, is ufually called a Bay. If it be but a very small part, or as it were, a fmall arm of the fea, that runs but a few miles between the land, it is called a Creek or Haven.

18. A Strait is a narrow paffage lying between two fhores, whereby two feas are joined together; as the Straits of Dover, between the British Channel and the German Sea; the Straits of Gibraltar, between the Atlantic and the Mediterranean Sea. These are all the neceffary terms used in Geography.

The names of the feveral countries, feas, and all the principal divifions of the earth, the reader will find expreffed upon the terreftrial globe.

To give a proper account of the produce of each country, the genius of the people, their political inftitutions, &c. is, properly, a subject of itself.

A DESCRIPTION OF THE GLOBES.

A globe is a spherical, or round body, whereon thofe circles, that are fixed, are drawn; those that are moveable, are fupplied by the brafs meridian, the wooden horizon, and the quadrant of altitude.

The appurtenances of a globe are, ift. the axes, reprefented by a wire run through both poles. 2. A brafs circle, reprefenting the first meri dian, wherein the globe turns on its axis. 3. A wooden frame, repre

fenting the horizon, on which the courfe of the fun is infcribed; and within which, the brazen meridian turns, by means of the notches. 4. The horary circle; it is fixed in the brazen meridian, in fuch a manner, as to make the pole its center. 5. The quadrant of altitude; which is a thin brafs plate, fcrewed to the brazen meridian, and graduated with 90 degrees, anfwering to one-fourth part of the equator. 6. The femi-circle of pofition; this is a thin narrow plate of brafs, exactly anfwering to one-half of the equator, containing 180 degrees. 7. The compass; it is a round circle, like a wheel, with 32 points iffuing from its center; one of which is a flower-de-luce, and points due north: it ufually ftands on the pedestal of the horizon.

The things above described are common to both globes; but there are fome others, which are peculiar, or proper to one fort of globe. The two colours, and the circles of latitude, from the ecliptic, belong only to the celeftial globe; alfo the ecliptic itself does properly belong only to this globe, though it is drawn on the terreftrial, for the fake of 3L 2 hofe

thofe that might not have the other by them. The equinoctial, on the celeftial globe, is always numbered into 360 degrees, beginning at the equinoctial point ; but on the terreftrial, it is arbitrary, where thefe numbers commence, according to the meridian of what place you intend for your firft; and the degrees may be counted, either quite round to 360, or both ways, till they meet in the oppofite part of the meridian,

at 180.

The globe is of great ufe to explain geography: is very eafy and pleasant to learners, and will explain a great number of problems; fome of which are the following,

THE USE OF THE TERRESTRIAL GLOBE.

PROBLEM I. To find the latitude and longitude of any given place upon the globe.

Turn the globe round its axis, till the given place lie exactly under the brazen meridian; then that degree upon the meridian which is directly over it is the latitude; likewife that degree upon the equator which is cut by the brazen meridian, is the longitude required from the first meridian upon the globe.

EXAMPLE. What is the latitude and longitude of Mexico, Pekin in China, and Cape Horn?

PROB. 2. The latitude and longitude being known, to redify the globes fit for ufe.

Raife the pole to the given latitude, as fuppofe London; then fix the quadrant of altitude in the zenith, and by the compass on the pedeftal fet the globe so that the brazen meridian may stand due north and fouth, according to the needle, and then it is done.

EXAMPLE. By the preceding problem I find the latitude of London to be 51 degrees north latitude; therefore I count 514 degrees from the pole downwards, and turn the meridian through the notches of the horizon till thofe 51 degrees come exactly to the uppermoft edge of the north point in the horizon; and then is the meridian rectified to the latitude of London.

2. Next rectify the quadrant of altitude, by fcrewing the edge of the nut that is even with the graduated edge of the thin plate, to 514 degrees of the brazen meridian counted from the equinoctial, which is the zenith of London; and thus is your globe rectified for the folution of fuch queftions as are to be wrought thereby in that latitude.

PROB. 3.

PROB. 3. The latitude and longitude being given, to find the place. Seek for the given longitude in the equator, and bring that point to the meridian; then count from the equator on the meridian, the degree of latitude given towards the arctic or antarctick pole, according as the latitude is northerly or foutherly; and under that degree of latitude lies the place required.

EXAMPLE. What is the name of that place, whofe latitude is 18° N. and longitude 761⁄2 W. ? Anfwer, Jamaica.

PROB.4. To find the difference of latitude between any two given places.

Bring each of the places propofed fucceffively to the meridian, and obferve where they interfect it; then the number of degrees upon the meridian, contained between the two interfections, will be the difference of latitude required; or, if the places propofed are on the fame fide of the equator, having first found their latitudes, fubtract the leffer from the greater; but if they are on the contrary fides of the equator, add them together; and the difference in the first cafe, and the fum in the latter, will be the difference of latitude required.

EXAMPLE. What is the difference of latitude between London and Rome; alfo between Paris and Cape Bona ?

The difference of latitude between London and Rome, is 90° 45"; and between Paris and Cape Bona, is 83°.

PROB. 5. To find the difference of longitude between any two given

plaçes.

Bring each of the places fucceffively to the meridian, and fee where the meridian cuts the equator. each time; the number of degrees contained between those two points, if it be lefs than 180 degrees, otherwife the remainder to 360 degrees, will be the difference of longitude required.

EXAMPLE. What is the difference of longitude between Rome and Conftantinople?

By working as above, you will find the difference of longitude to be 19° (which are reduced into miles, by multiplying the degrees by 60, and allowing for every minute, one mile) makes 1140 miles for their distance.

PROB. 6. The day of the month being given, to find the fun's place in the ecliptic, and his declination.

First, to find the fun's place, look for the day of the month, given in the kalendar of months, upon the horizon; and against it, you will find that fign and degree of the ecliptic, which the fun is in. The fun's place being thus found, look for the fame in the ecliptic line, which is drawn upon the globe, and bring that point to the meridian; then that degree of the meridian, which is over the fun's place, is the declination required; which is either north or fouth, according as the fun is in the northern or fouthern figns: thus,

Sun's

PROB. 7. To find the angle of pofition of places; or, the angle formed by the meridian of one place, and a great circle paffing through both the places.

First, rectify the globe, for the latitude and zenith of one of the given places; then bring the faid place to the meridian, and turn the quadrant of altitude about, until the fiducial edge thereof cuts the other place; and the number of degrees upon the horizon, contained between the faid edge and the meridian, will be the angle of pofition fought.

Thus, the angle of pofition at the Lizard, between the meridian of the Lizard, and the great circle paffing from thence to Barbadoes, is 69 degrees fouth-wefterly; but the angle of pofition between the fame places, at Barbadoes, is but 38 degrees, north-easterly.

SCHOLIUM. The angle of pofition between two places, is a different thing from what is meant by the bearings of places; the bearings of two places is determined by a fort of spiral line, called a rhumb line, paffing between them in fuch a manner, as to make the fame or equal angles, with all the meridians through which it paffeth. But the angle of pofition is the very fame thing with what we call the azimuth in aftronomy; both being formed by the meridian, and a great circle, paffing through the zenith of a given place, and a given point, either in the heavens, then called the azimuth, or upon the earth, then called the angle of pofition.

From hence may be difcovered the error of that geographical paradox, viz. if a place, A, bears from another, B, due weft, B fhall not bear from A due eaft; for if it be admitted, that the eaft and weft lines make the fame angles with all the meridians through which they pass, it will follow, that these lines are the parallels of latitude for the path defcribed in travelling from east to weft, is the continuation of the furface of a cone, whofe fides are the radii of the sphere, and bafe the parallel of latitude of the traveller; and it is evident, that all the meridians cut the faid furface at right (and therefore at equal) angles; whence it follows, that the rhumbs of eaft and weft are the parallels of latitude; though the cafe may feem different, when we draw inclining lines (like meridians) upon paper, without carrying our idea any further.

PROB, 8. To find the Antaci, Periæci, and Antipodes, to any given place.

Bring the given place to the meridian, and having found its latitude, count the fame number of degrees on the meridian, from the equator towards the contrary pole, and that will give the place of the Antœci. The globe being ftill in the fame pofition, fet the hour index to 12 at noon; then turn the globe about, till the index points to the lower 12;

the

the place which then lies under the meridian, having the fame latitude with the given place, is the Pericci required. As the globe now ftands, the Antipodes of the given place are under the fame point of the meridian that its Antoci ftood before.

EXAMPLE. Required the Antoci, Pericci, and Antipodes, to London, whose latitude is 51° 30′ North.

That place which lies under the fame meridian, and in the latitude of 51° 30' fouth, is the Antoci. That which lies in the fame parallel with London, and 180° of longitude from it, is the Perioci, and the Antipodes is that place whofe longitude from London is 180°, and latitude 51° 30' fouth.

PROB. 9. The hour of the day at one place, being given, to find the corresponding hour, or what o'clock it is at that time in any other place.

The difference of time between two places, is the fame with their difference of longitude; wherefore, having found their difference of longitude, reduce it into time, by allowing one hour for every 15 degrees, &c. and if the place, where the hour is required, lies eafterly from the place where the hour is given, add the difference of longitude, reduced into time, to the hour given, and the fum will be the hour required; and if the place lies wefterly, fubtract the difference of longitude, reduced into time, the remainder will be the hour required. Or,

Bring the place, where the hour is given, to the meridian, and fet the hour index to the given hour, then turn the globe about, until the place, where the hour is required comes to the meridian, and the hour index will point out the hour at the said place.

PROB. 10 The day of the month being given, to find those parts on the globe where the fun will be vertical, or in the zenith that day.

Having found the fun's place in the ecliptic, bring the fame to the meridian, and note the degree over it: then turning the globe round, all places that pafs under that degree, will have the fun vertical that day.

PROB. II.