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 196
Fig. 6. … Fig. 7. disc can be rotated about their common axis and set in any position. Theouter ring carries the time scale A and is graduated to log i/T, T in daysfrom 20 to 200. The movable ring has a joint scale for P, the principal I7° SECTION F (position B), and I, the interest (position C), being…
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