face of one-half of the globe is laid down as if it were viewed by an observer at an infinite distance, where the rays of sight are every where parallel to one another, and perpendicular to the points of the surface laid down. In this case, the parts about the centre of the hemisphere are shown with some accuracy, but those towards the circumference are more and more contracted as they approach the margin.

2d. The stereographic projection, founded on the principles of representing a solid body on a plane surface, assumes the eye to be placed on the surface of the globe, supposed to be transparent as a ball of crystal, and looking to every point of the opposite surface. In this case a contrary defect occurs, for the parts of the hemisphere situated towards the centre, are represented smaller than they ought to be, while those towards the circumference are enlarged beyond their due bounds.

3d. The globular projection is an attempt to combine the two former methods by choosing a point of view neither on the surface of the globe, nor at an infinite distance from it. This point of view is supposed to be removed from the surface of the globe, to a distance equal to the sine of 45 degrees of a scale, of which the radius is that of the globe itself. This position of the point of sight affords a projection in which the defects taken on a general view are the least possible, and on this account, the globular projection is now commonly adopted in representations of the globe of the earth.

THE

THE

MODERN PRECEPTOR.

CHAPTER X.

DRAWING, PAINTING, ENGRAVING,

&c.

A DISP

DISPOSITION to form images of central objects is congenial with the human mind, evincing itself in the earliest youth and in all stages of civilization: to trace such images by a simple outline is properly termed Drawing, and the application of one or more colours to complete the resemblance of the original object, is called Colouring or Painting.

1st. OF DRAWING.

The essence of good drawing is to trace on paper, or other substance, a correct rescinblance of an object as seen from one fixed station or point of view, observing carefully to represent each part or member of the object or figure in the due proportionate magnitude which the corresponding parts of the original bear the one to the other, and to the whole object taken together.

In drawing a square, a circle, or any other geometrical

figure,