An encyclopaedia of architecture, historical, theoretical, & practical. New ed., rev., portions rewritten, and with additions by Wyatt Papworth (1888)
Gwilt, Joseph, 1784-1863, Papworth, Wyatt Angelicus Van Sandau, 1822-1894 · London Longmans, Green · leaf 343
es, and that in those which have plane sinfaces, their faces unite so as to form solid angles.We have also observed that at least three plane angles are necessary to form a solid angle;wlience it is manifest that the most sim])le of all the solids is a ))yrainid with a triangularbase, which is… … the three triangles whose faces aie inclined (^.17. 478.); by which we obtain a figurecomposed of four triangles. To cut this out in jiajier, for instance, or any other flexiblematerial, after bending it on the lines ah, be, uc, which form the triangle at the base, thethree triangles are turned up…
Architecture · Architects
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