Scale RulesCalculating Rules
In addition to length measurements, scale rules could be marked with aids for calculation. Perhaps the most notable rule of this type was Gunter's scale, which was similar to a sector or a slide rule. Gunter's scales are named after Edmund Gunter, a 17th-century English mathematical practitioner who figured out how to put a table of logarithms on a rule so that logarithmic calculations could be made with the aid of dividers. These instruments were especially handy for mathematicians and navigators.
The mathematics collections contain several other objects, ranging from the 18th to the 20th centuries, that were used to simplify computations for tasks including designing sundials, keeping track of calendar dates, and plotting data for aeronautical engineering. A few of these rules were designed specifically for positioning artillery.