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This part of the Subject, if a little attention is paid it, will be found to facilitate the study of Geography, in an uncommon degree, and is perfectly simple. I have taught children, as well as adults, who knew not a single outline in this Science, to be able to answer the problems on the Terrestrial Globe; to understand all kinds of Maps; to delineate a Map or Hemisphere, and to insert every place with correctness, in eight lessons; and this is what many are not able to do who have been learning for years.
I shall endeavour here to teach you how to make use of your Room, as a Globe or concave sphere; or if you like it better, imagine it to be hung round with the Maps of the four quarters of the world.
Every square Room must be equal to the circumference of a circle, or 360 degrees, so that each Wall will represent the quarter or quadrant of a circle; and according to this plan each Wall must be divided into nine parts, called meridians, agreeable to the Map, before you.
Observe then, that the meridian of London must be placed in one corner of the Room, then the two Walls on the right hand will be East longitude, and the two Walls to the left will be West lon. so that from the corner in which the meridian of London is placed, to the next corner on the right havd
Wall will be 90 degrees East; and to the corner of the second Wall on the right will be 180 deg. East. The first Wall to the left will be 90 deg. W. and the second Wall to the left will make 180 deg. W. these added will be equal to 360, the cireumference of a circle, as I before noticed.
You must fancy that the Room beneath you, is of the same shape and dimensions with the one in which you sit; then that will represent your Southern, and the one where you are, the Northern Hemisphere. The Floor on vhich you stand will be the Equator; the centre of the ceiling over head, will denote the North Pole, and the centre of the Floor in the Room beneath, will represent the South Pole; this is on the plane of the Equator, so that you have the Poles in the zenith and nadir; i. e, the one over the head, and the other under the feet, and the Equator parallel with the horizon. But to set aside all these technical terms, it is nothing more as I before observed, than to imagine the Maps of the different countries drawn on your Walls, aud this is easily done by the following rules.
By looking at the Map you will perceive that the numbers begin with 0,* from the opening, and increase upwards on the straight line to 60, (the top of the Wall) from 60 the lines converge, all meeting at 90 degrees, the N. Pole; so that the first 60 degrees are on the Wall, and the remaining 30, on the ceiling, making together 90 degrees N. lat.
The opening of the Map, where the line of figures runs through the middle, is the place where the imaginary Floor comes, dividing the upper from the lower Hemisphere, or in other words, the Northern Room from the Southern; so that the lower half of the Map gives you the divisions
of a Wall in the Southern Room; having also 60 degrees on the Wall, and the other 30 on the Floor, beneath, converging to the middle of the Floor, which is called the South Pole, or 90 degrees South Latitude.
You perceive then, that this Map gives you the divisions of a Wall in the Room which you are, and also the same Wall in the Room beneath you ; and you must divide, or fancy the other Walls divided, in the same manner, by imaginary lines drawn from the middle of the ceiling over head, to the lines on the Wall, passing through the Floor down to the middle of the Floor in the Room below; and these lines will nearly correspond with the lines on a Globe or Hemisphere. If
you stick or pin figures, against the Wall, as 10, 20, &c. to 180, East and West, from the meridian of London, just one ninth part of the Wall asunder, they will be a sufficient guide to the eye for the meridians.
Having fixed on one corner of the Room for the meridian of London, measure the height of the Room, and divide it into six parts, then stick, or pin figures in that corner, thus, 10, 20, 30, 40, 50, 60, to the top of the Wall, and this will represent the latitude, as far as 60 degrees, and serve as a guide to the eye all round the room.
.. To get by heart a great number of longitudes and latitudes is the most essential part of Geography, and yet the most neglected. If a person is acquainted with these, whether it be bays, capes, harbours, towns, or what not, he can draw his parallels of longitude and latitude, and immediately insert them without a Map, Globe, or any thing before him. A copious table of the lon. and lat. of places follows.
The word, at, set off at the beginning denotes a place to be N. lat. and wherever the word, with, occurs, shews the place to be S. lat. The word, was, means W. lon. and, is, East; so that three short words give you the lon. and lat. of a place, and by these means, the lon. and lat. of two or three hundred places may be soon learned. The first word stands for the lon, and the second for the lat.
At Aberdeen, Scotland, was due leap. The word, at, denotes N.lat. the was, W. lon. due, 2 deg. lon. leap, 57 N. lat.–At Alexandria, in Egypt, is gauze fib, is, signifies E. lon. (gauze fib) are 30 lon. and 31 N. lat.-by attending to the above observations you cannot fail to understand it so far.
I will now proceed to direct you how to transfer any place or country from a Map, &c. to the Walls of your Room, and this being once done, you will
carry them with your eye into any apartment you go.
Observe, in the Map which we have been speaking of, a dotted line at the top part, 10 deg. or one line from the meridian of London) to the W. or left hand; this is to take the whole of Europe into the top part of the Map, as that quarter extends from about 10 deg. W. to 62 E. and is separated from Africa by the Mediterranean and the straits of Gibraltar, running between that town and Tangiers, in Africa.
Look on the Map and you will see these towns nearly opposite, the first has about 5 deg. and the other 6 W. lon. and but a few minutes difference of lat. therefore the same word will express the lat. of both, (36 deg.) You will find them alphabetically arranged in the table.
To put these places on the Wall.
Five deg. of W. Ion, is just half way from the meridian of London, West, to the next division ; and 36 degrees N. lat. will be a little more than half way between 30 and 40 in the hight of the Room. The lon. and lat. of Petersburgh is gaze maze, i. e. 30 deg, E. lon, and 60 N. lat. look to the right of the meridian of London for 30, and at the top of the Wall you have 60, the lat. see it on the Map.-Nankin, China, is 118 E. lon. and 32 N. lat." The corner of the first Wall to the right of the meridian of London, will be 90 degrees; to the next division on the second Wall be 100, the next 110, and to the next 120; we find the lon. then, near the meridian of 120 E. and a little more than half way up the Wall we have 32 N. lat. Kingston, in Jamaica, was pope bare, 77