According to the manual:
This instrument has two Logarithmic Scales, one 30 inches long and the other, a spiral, 75 feet long. Two results to every problem can be read. The result given by the short scale can be read to three figures and the result on the 75 foot scale can be read to five figures as 98,687.
The "Atlas Slide Rule" will handle three factors at one setting and hold the result, two additional factors can be used with this result at each additional setting.
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The "B side" (not shown yet) has one cursor, three degrees-sines-tangents scales (one for each of 0–30, 30–60, and 60–90 degrees), and a table of decimal equivalents of fractions at intervals of 1/64.