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The Use os the Terreßrial Glohe .

meridian, on that side which is above the south point of the horizon:then count from the equator, on the braten meridian, to the degree ofthe given latitude, towards the north or south pole, according as thelatitude is north or south; and under that degree of latitude on themeridian, you will have the place required.

PROBLEM III.

To find the difference of longitude, or difference of latitude, between any

two given places.

Bring each of thefe places to the brafen meridian, and see what itslatitude is: the leffer latitude subtracted from the greater, if both placesare on the fame side of the equator, or both latitudes added together,if they are on different sides of it, is the difference of latitude required.And the number of degrees contained between thefe places, reckonedon the equator, when they are brought feparately under the b rasenmeridian, is their difference oFlongitude; if it be lefs than 180: butif more, letit be subtracted from 360, and the remainder is the dif-ference of longitude required. Or,

Having brought one of the places to the brafen meridian, and fet thehour-index to XII, turn the globe until the other place comes to thebrafen meridian, and the number of hours and parts of an hour, pastover by the index, will give the longitude in time; which may beeasily reduced to degrees, by allowing 15 degrees for every hour, andone degree for every four minutes.

N. B. When we fpeak of bringing any place to the brafen meridian,it is the graduated side of the meridian that is meanti

PROBLEM IV.

Any place being given, to find all those places that have the fame longitude

or latitude with it.

Bring the given place to the brasen meridian, then ali those placeswhich lie under that side of the meridian, from pole to pole, havethe fame longitude with the given place. Turn the globe round itsaxis, and all those places which pafs under the fame degree of the me-ridian that the given place does, have the fame latitude with thatplace.

Since

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