Hydrostatic balance by Ramsden used in 1789, in experiments conducted by the Royal Society to determine accurately the specific gravity of mixtures of water and spirit. 24" beam weighs to 10 lbs, sensitive to less than 0.01 grain. Pans and some other parts missing, two small ivory knobs of drawers broken.

The London instrument maker Jesse Ramsden made this analytical balance. It was used to made hydrostatic measurements for experiments conducted by the Royal Society in 1789 to determine accurately the specific gravity of mixtures of water and spirit. The two-foot beam weights to 10 lbs and is sensitive to less than 0.01 grain.