Benjamin Huntsman

Benjamin Huntsman is able to make satisfactory cast steel after many experiments, in clay pots or crucibles holding about thirty-four pounds of blistered steel each.

A flux is added and they are covered and heated by means of coke for about three hours.

The molten steel is then poured into molds and the crucibles reused.

The local cutlery manufacturers refuse to buy it as it is harder than the German steel they are accustomed to using.

For a long time, Huntsman will export his whole output to France.

Born the third son of a Quaker farmer in Epworth, Lincolnshire, his German parents had emigrated only a few years before his birth.

Huntsman started business as a clock, lock and tool maker in Doncaster.

His reputation enabled him to also practice surgery in an experimental fashion and was also consulted as an oculist.

Huntsman had experimented in steel manufacture, first at Doncaster, then moved in 1740 to Handsworth, near Sheffield.

John Harrison has workied on his third 'sea clock' to solve the problem of determining longitude for seventeen years, but despite every effort it does not perform exactly as he wishes.

The problem is that, because Harrison does not fully understand the physics behind the springs used to control the balance wheels, the timing of the wheels is not isochronous, a characteristic that affects its accuracy.

Despite this, it has proved a very valuable experiment as much has been learned from its construction.

Certainly in this machine Harrison has left the world two enduring legacies—the bimetallic strip and the caged roller bearing.

After steadfastly pursuing various methods during thirty years of experimentation, Harrison moves to London, where to his surprise he finds that some of the watches made by George Graham's successor Thomas Mudge keep time just as accurately as his huge sea clocks.

It is possible that Mudge had been able to do this after the early 1740s thanks to the availability of the new "Huntsman" or "Crucible" steel produced by Benjamin Huntsman sometime in the early 1740s, which enables harder pinions but more importantly, a tougher and more highly polished cylinder escapement to be produced.

Harrison now realizes that a mere watch after all can be made accurate enough for the task and is a far more practical proposition for use as a marine timekeeper.

He proceeds to redesign the concept of the watch as a timekeeping device, basing his design on sound scientific principles.