The original George I barometer in a unique silver and ebony case made by Daniel Delander in the 1720s was stolen from Ramsbury Manor during a raid by the Johnson gang in 2008 and has not been recovered.
It had been bought for £275,000 in 1992 by property developer and connoisseur collector Harry Hyams (1928-2015).
Matthew King of Time Traveller Clocks in Surrey was asked to create a replica of the barometer by a client who had seen it pictured in a magazine.
Time Traveller had previously completed a copy of the earliest known all-wood clock made by John Harrison in 1713.
King said: “Conserving an object is often a challenge, however, replicating a completely lost object is a considerably trickier proposition.”
The barometer took several years to complete with King taking his direction from two photographs of the original. The silver elements required modelling and casting: the two Corinthian column capitals are built from three separate castings.
The workshop is currently working on a second replica which will be offered for sale.