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 141
m after a check had been imposed,then injurious results would easily follow improper usage. To prevent this,the crank is constructed in a special way. To the crank shaft is fixed a disctx, and above it a rotary disc t2, to which is attached the crank K (fig. 52) ;between them is placed a spiral… … Fig. 52.—[\ actual size.) Con-struction of the crank.
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