Worthen, William Ezra, 1819-1897, [from old catalog] ed · New York, Appleton · leaf 684
Fig. 1619. Fig. 1620. Fig. 1621. the two-centred pointed, the equilateral (Fig. 1621), the lancet, and the ob-tuse. Of the first, the radii of the segments forming the arch are equal to thebreadth of the arch, of those of the lancet longer, and of the obtuse shorter. Of the complex arches, there…
Mechanical drawing
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