Nature 121, 276-276 (25 February 1928) | doi:10.1038/121276a0

A Graphic Table combining Logarithms and Anti-Logarithms: giving directly without Interpolation the Logarithms to Five Places of all Five-place Numbers and the Numbers to Five Places corresponding to all Five-place Logarithms; also a Graphic Table as above reading to Four Places

L. J. C.

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THIS volume presents a 5-figure logarithmic and a 5-figure anti-logarithmic table in graphical form. A typical page is that providing the logarithms of the numbers 40,000 to 43,000. Twenty-five horizontal lines are divided on their upper side into 3000 parts, each about one mm. lomg. Every tenth division is numbered, thus forming a linear scale from 40,000 to 43,000. The lower side of each line is graduated logarithmically, these graduations extending from 0-60206 to 0-63347. Hence the logarithm of a number may be found to five decimals without interpolation by locating the point in the upper scale corresponding to the number, and then reading the lower scale at this point. The reverse process serves for the finding of a number from a given logarithm.