He accomplished this by the use of a vertical screw pump which lifts the water to a reservoir, from which it passes through the meter to be tested and thence over a weir, where it is measured.

After seven years at the National Meter Company, Nash began the study of the gas engine and subsequently received sixty or more patents covering their design and operation.

The engines were directly connected to dynamos and although they operated under violently fluctuating load conditions, they ran well, both in regulation and economy modes.

The company never prosecuted infringements of their gas engine patents, and Nash's efforts were mostly unappreciated, for those at the head of the business not only failed to push his developments, but continually curtailed his authority.

When Nash conceived the idea of a new type of vacuum pumping equipment, he decided not to assign the patents to the National Meter Company, but to manufacture the product himself.

After three years of designing and testing, manufacture was started at a factory over a shop on Water Street in South Norwalk.

In 1911, Nash and his family moved to South Norwalk, and three years later he severed his connections with the National Meter Company to devote his entire time to his own firm.

In 1909 Irving C. Jennings was hired part-time to help in testing pump technology, receiving pay in the form of company stock.

In that year, Nash's eldest son Douglas graduated from Stevens Institute of Technology, and it was his first task to superintend the construction of the new factory.

The five years from 1918 to his death on November 17, 1923, Nash saw his company grow to be a prosperous, well-established concern, and was he able spend most of his time in his laboratory, where he could work out his many inventions and ideas.

[citation needed] In 1921 Nash's alma mater the Stevens Institute recognized his outstanding achievements by awarding him the degree of Doctor of Engineering (E.D.