The American house-carpenter; a treatise on the art of building, and the strength of materials (1867)
Hatfield, R. G. (Robert Griffith), 1815-1879 · New York, J. Wiley · leaf 59
to ac; then h d will be tliomean proportional between A and B. That is, <3^ 5 is to 5 (^ ash d istoh c. This is nsaally stated thus—«^ h :1? b::hd ih c,and since the product of the means equals the product of theextremes, therefore, ahxh G= Td\ Tliis is shown geometri-cally at Art. 105. CONIC… … Fig. 79. \ais ahc, Fig. 79;) and the base will be a semi-circle. If a conebe cut by a plane in the direction, e /, the section will be anelUjjsis / if in the direction, m Z, the section will be 2i>parabola ;and if in the direction, r c, an hyperbola. (See Art. 56 to 60.) Ifthe cutting planes be…
Carpentry · Architecture
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