The examples now given have had reference only to one peculiar position of the lines to be drawn; that is, they have all been horizontal, or all perpendicular or oblique; placed in the same relative position to one another. We now give an example where the lines go in different directions with respect to one another. Thus in drawing the lines b a, a f, d c, and c e, Fig. 5, care must be taken to have the lines perpendicular to one another; that is, supposing the lines a b, c d, to be drawn first, the horizontal lines a f, c e, must be drawn so that the points or ends f e shall be neither above nor below the ends or points a, c—that is, f and e must be exactly opposite a and c. In the present case, no mechanical aid is allowable; the eye is to be the only guide. Attention should also be paid to keeping the exact distance between the lines a b, a f, and c d, and c e. The pupil must not imagine that all these modifications of lines are worthless; a little patience and reflection will suffice to show him that they are, in truth, part of the groundwork, without which he can never hope to rear the superstructure of perfect drawing. We now proceed to a little more interesting labor, where simple figures are to be drawn; these, however, being neither more nor less than the lines already given variously disposed. Draw the lines a c, b c, Fig. 6, meeting in the point c; these form a certain angle; care should be taken to draw the lines as in the copy. Next draw the horizontal line a b, Fig. 7, and a figure is formed which the pupil will at once recognize. Draw the horizontal line a b, Fig. 8; perpendicular to it, from the ends a b, draw the lines a c, b d, taking care that they are of the same length as a b; draw the line c d, a square is at once formed. As it is an essential feature in this form that all the sides are equal, if the pupil, after drawing it, perceives any inequality therein, he should rub it out and proceed to another attempt. Some little practice should be given to the delineation of squares, angles, &c. If a parallelogram or oblong—vulgarly called an oblong square—is wished to be drawn, it may be done by making two opposite lines shorter than the others; the line e denotes the fourth outline of an oblong, of which the side is a b. If two oblongs be drawn, care being taken to have the inner lines the same distance within the outer ones all round, by adding a narrow line outside these, as in Fig. 9, the representation of a picture-frame is obtained; the diagonal lines at the corners, as at a and b, being put in to represent the joinings at the corners of the frame, the "mitre" joints, as they are termed. By first drawing the simple outlines, as in Fig. 10, the foundation of a door is obtained by filling in the extra lines, as in the figure.
Fig. 6.
Fig. 7.
Fig. 8.
Fig. 9.
