Baumé scale [bow m-ay] noun
A hydrometer scale that measures the density of liquid. There are two hydrometers: one measures density in liquids that are heavier than water, the other measures liquid that is lighter. This method of measurement is named after French chemist Antoine Baumé (1728-1804). Although some chefs still use the Baumé scale that provides measurements in degrees, many now use the Brix scale, which uses a much simpler expression in percentages.
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The Baumé scale is related to the saccharimeter, which measures the sugar concentration in liquid.