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 229
Fig. S.—Earliest form of the Rolling Planimeter. This was constructed in 1883. Rolling-Sphere Planimeter … Fig. 9.—Rolling-Sphere Planimeter. Fig. 9 represents the instrument to about half size. The guide line of the pivot of the tracer arm F is, as with all linear plani-meters, a straight line. The instrument rests on the diagram at threepoints, the two rollers R and the tracer F or its support s. In…
