The carpenter and joiner's assistant : being a comprehensive treatise on the selection, preparation, and strength of materials, and the mechanical principles of framing, with their application in carpentry, joinery, and hand-railing : also, a course of instruction in practical geometry, geometrical lines, drawing, projection, and perspective : and an illustrated glossary of terms used in architecture and building (1860)
Newlands, James, 1813-1871 · Glasgow : Blackie and Son · leaf 71
of one of them gives the others. There the points I and H let fall perpendiculars on their is necessarily a proportion between the triangle A b c bases produced. If each of these pentagons were raised (Fig. 285) and ABC (Fig. 284), since the first is the vertically on its base, the horizontal… … jection of AG; but A G is a part of A H, and the projec¬ reason of the regularity of the figure, it is easy to see that tion of that line is required for one of the faces ot the the six other faces will be similar to those already drawn, solid ; therefore, as A G : A g : : A H: x, which may be…
