Page:Archaeological Journal, Volume 4.djvu/36

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24
RULES FOR CONSTRUCTING A PINNACLE.

Archaeological Journal, Volume 4, 0036a.png

Fig. 6.

In all these figures the letters a b c d refer to the square block or plinth of the pinnacle, and e f g h to the shaft, and the intention so far is to shew the breadth and depth of the panel, and the next, fig. 6, shews the method of finding the hollow moulding of the panel. This is found by dividing the line n i into three equal parts, taking two of these parts, and marking the distance on the line at o, and then with the same distance as a radius and o as a centre striking the curves required.

Archaeological Journal, Volume 4, 0036b.png

Fig. 7.

Fig. 7 shews the mode of laying down the crockets. This is done by drawing lines parallel to the diagonal of the square through n n——n n, and producing them as far as p q r s, then take double the width of p r and set it off from n towards p, and this gives the projection of the crocket.

Archaeological Journal, Volume 4, 0036c.png

Fig. 8.

Fig. 8 shews this without the working lines.

The next figures refer to the elevation of the pinnacle, and we are directed to draw an upright line, which is called the middle ridge, and on this to lay out six times the distance a b, fig. 1, which gives the height of the pinnacle, so that the height of the pinnacle is six times the breadth of the square block or plinth. These divisions are to be marked I, II, &c, (fig. 9.) and form a scale for the remaining ones. In the next, fig. 10, the half width of the original block a b, is to be set out on each side the middle ridge. This gives the size of the stone out of which the shaft of the pinnacle is to be cut, and the next, fig. 11, shews the mode of transferring the measurements of the plan to the elevation: the first square (to I) being taken for the plain block or plinth, which is chamfered down to the thickness of the shaft, the width of the panel is then transferred from the plan. Fig. 12 shews the shaft without the working lines.

The next figures refer to the drawing of the spire of the pinnacle. We are directed to draw the middle ridge, and to make the height seven times the length of a b, so that the proportion of the spire is to the shaft as 7 to 6. The base is to be made equal to the line e h, fig. 6, and the top to twice that of n o, as in fig. 12. The gablet is then formed by