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first class only draw right lines, triangles and perpendiculars. The corrections are made with a rule, and dividers.

The four first figures drawn above, relate particularly to the first eight propositions. To ascertain if the line be straight, let the monitor draw a line through it or near it with a rule. To ascertain if a line be cut into equal parts, measure the parts with the dividers, if the eye be not sufficiently practised to detect the errors without their assistance.

PROPOSITIONS.

1. Draw a right line (that is, a straight line.) fig. 1.

2. Draw a right line and divide it in the centre. fig. 2.

3. Draw a right line and cut it into quarters. fig. 3.

4. Draw a right line and lengthen it a much farther. fig. 2.