Joshua Haskins
c.1721 Joshua Haskins proposed the use of mercury to provide a manometric seal for pump pistons, in place of leather sealing collars, thereby avoiding leakage of air or water, and reducing losses by friction which led to inefficiency and jerkiness. He carried out an experiment at the house of John Theophilus Desaguliers, which Desaguliers repeated before the Royal Society using a model. Haskins died shortly thereafter, and Desaguliers continued with the development work.[1]