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Meridians at equal Angles ; these and other Properties it hath in common with the Globe.

2. From hence 'cis easy to conceive that any Diftance on any Part of this Chart is capable of being measured by a Scale of equal Parts, whether in a Great Circle, Rumb, or Parallel ; and therefore needs not so much of Calculation as other Charts do.

3. Now because this Chart expresseth the several Parts of the Superficies of the Earth in their due Position and Magnitude, therefore the Globular Projection is much more proper for Maps, as well as Sea Charts, than either the Stereographic, or Mercator's Projections.

4. As to the Method of making or constructing this Globular Chart; it consisteth of these three Things: First, in drawing the Parallels ; Secondly, in describing the Meridians; and Thirdly, in laying down the Rumbs in a due manner. The first part is performed with ease, but the two latter with more difficulty. The Manner of doing each is as follows.

1. To draw the Parallels.

In the Middle of the Paper designed for the Chart, draw the Line AC, and graduate it into go Degrees, from a Scale of equal Parts ; and on C as a Center, thro' every five or ten of those Degrees describe the Arches of Circles within the designed Limits of the Chart ; those Circular Arches will be thus equidiftant and concentric, and consequently they will be the Parallels of Latitude ; which were to be drawn.

2. To describe the Meridians.

In order to this, we must know the Proportion of their Inclination to each other as they approach the

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Poles, and this being equal in equal Degrees of Latitude ; all the Meridians that can fall within the Com. pafs of your Chart may be easily described by the following Table ; which sheweth in what Proportion the Distance of Meridians diminish as they go from the Equator. Suppose therefore two Meridians distant from each other in the Equator one Degree or sixty Italian Miles, then their Distance from each other in every Degree of Latitude is as here set down.

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The Use of this Table in describing the Meridians on this Chart is thus ;

Suppose

Suppose the Chart begins from the Equator ( as that I have here subjoined for Example doth ) Æ Q, and graduated from the fame Scale as the Meridian AC. Then take your Sector in hand, and with the Compasses take AB = 10o = A E, and set it over parallel-wise from 60 to 60 in your Sector ; the Sector remaining thus, take therefrom the Parallel Distance of 59° ( being in the Number in the Table answering to the Latitude of 100 ) and set it on the Parallel of 10 Degrees from E to a, b, c, each ways as far as the Limits of your Chart will admit ; then take the Parallel Distance of 56° 24', and set it each way on the Parallel of 20 Degrees ; then take 51° 56' and set it off each way on the Parallel of 30 Degrees ; on the Parallel of 40 Degrees set 460 00 on each side the graduated Meridian ; and thus proceed by taking the tabular Number from the Sečtor, and setting it on any other Parallel as far as the Chart requires, and thus shall you have the Points in every Parallel of 10 Degrees, through which the several Meridians must pass ; you may do the like on the Parallel of every fifth Degree of Latitude ; and haveing thus pointed the leveral Parallels on the Chart, you may with an even Hand, or a Bow for such Purposes, describe Lines through those Points, which when drawn, will appear to be Curvilineal, and equally inclining to each other, and are therefore the Meridians required to be drawn ; having the fame Properties with those on the Globe it self.

2. To describe the Rumbs.

This may be done several ways ; but the best way is by a Projection of the Rumb, or Rumbs required on a Mecartor's Chart ; for they being there all straight Lines, are very expeditiously drawn ; and

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