These days, we have become so used to computers, mobile devices and hand held or calculators for our day-to-day activities, so much so that some of us may have forgotten how we got by doing the more complex calculations back in those days where the hand held calculator did not exist. I myself had almost forgotten this myself until I dug up a book which accompanied me during my secondary school days and when I sat for my “O” level examinations: a book of Logarithmic Tables or the “Log Book” as we used to refer to it in school. I am not sure how long they were used for, but by the time my sister was sitting for her “O” level examinations, she had already been using a hand-held calculator to help with the more complex multiplications, divisions, and trigonometric calculations.
I think most of us back then had a wonderful time with it … some probably used it to sneak in mathematical formula for the exams. The Log Book actually helped many of us to appreciate some of the mathematical concepts better such as the use of logarithms and interpolation (of which we had to master to be able to successfully make use of the Log Book), where these days we are used to having numbers appear at the touch of a button without really putting much thought into it.
Complex multiplications (or divisions) could be done by converting numbers into a logarithm, being the exponent that a base number is raised to give the number. This simplified multiplications and divisions as the exponent could then be added or subtracted and the resultant being reconverted back (antilogarithm) to a number. There were also tables for sines, cosines and tangents as well as for square roots and hyperbolic functions in the Log Book. I know it sounds like a tedious process but it made a world of difference when access to a calculator was limited.