A text book of geometrical drawing, for the use of mechanics and schools, in which the definitions and rules of geometry are familiarly explained (1849)
centres are in the springingline. Figure 1.—The Lancet Arch. When the length of the span A. B is much less than the lengthof the chord A, C, as in the diagram^ the centres for striking thecurves will be some distance beyond the base^ as shewn by therods; the joints all radiate to the opposite… … /■?(/. J /)(/. /
