Modern instruments and methods of calculation : a handbook of the Napier Tercentenary Exhibition (1914)
Horsburg, E. M. (Ellice Martin), Napier Tercentenary Exhibition (1914 : Edinburgh, Scotalnd) · London : G. Bell · leaf 297
sz+d3 =0. Here X/X^/Y^/ZA is a straight line, and XXX, X/X, etc., arestraight lines perpendicular to it. We have X1,X1=Y1Y1=Z1Z1=il and X101=x, Y101=y> Z101=z. On X/X we lay off X1A1=*1 and draw AjX, to meet Y/Y in Plf YXYin^j, and OxO in Fv On PXY we lay off P1B1=61 and draw BjY, to meet Z/Z in… … Fig. 6. The figure indicates also similar constructions for a2x-\-b2y-\-c2z-\rd2 and a3x-\-b3y-\-c3z-\-d3,showing that these are represented by 02D2 and 03D3 respectively. INSTRUMENTS OF CALCULATION 269 If now x, y, and z be successively or simultaneously varied so that D1;D2) D3 coincide with 0„…
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