HMSO Subtabulation report - 1955 9 of 29
This government report describes how to interpolate tables using hand calculators.
Tables were used extensively for many applications until computers and small calculators became available. Tables can be much shorter if you knew how to interpolate accurately between the given values. See the tables of 20-figure logarithms.
Tables were used for navigation, design, and many areas where we would now compute what we want directly.
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