The Westphal Specific Gravity Balance

The Westphal specific gravity balance is a device that will measure the specific gravity directly if water is one of the liquids. It applies two concepts  

The mass of a floating object is equal to the mass of the liquid it displaces. 

If a body of constant mass is immersed in different liquids, then the corresponding apparent loss in weight of the body is proportional to the masses of the equal volumes of liquid that the body displaced. 

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