Hydrometer conversion table

Twaddell Hydrometer. This hydrometer, which is used only for liquids heavier than water, has a scale such that when the reading is multiplied by 5 and added to 1000 the resulting number is the specific gravity with reference to water as 1000. To convert specific gravity at 60°/60°F to Twaddell degrees, take the decimal portion of the specific gravity value and multiply it by 200 thus a specific gravity of 1.032 = 0.032 X 200 = 6.4° Tw. See also special table for conversion to density and Baume scale. 

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