A fine and rare George Adams Senior pyrometer, English, Mid-18th century,

This lot has been removed from the website, please contact customer services for more information

Lot 41
A fine and rare George Adams Senior pyrometer,
English, Mid-18th century,

Sold for £ 27,500 (US$ 33,636) inc. premium
A fine and rare George Adams Senior pyrometer, English, Mid-18th century,
Signed on the dial, 'Made by George Adams Instruments maker to His Majesty's Office of Ordnance at Tycho Brahe's Head in Fleet Street London', the steel platform supported by two brass brackets mounted with one of five metal bars; silver, copper, brass, iron and lead and engraved on each bar, one end resting against adjustable screw, the other against a blued steel lever attached by a chord, pulley and weight to indicate changes in length against circular dial with pointer, on mahogany base, 12 1/2 ins (32cm)

Footnotes

  • The pyrometer was originally invented by Wedgwood for use in his kilns and was first referred to as any instrument associated with a measure of heat. Subsequently it came to refer to a means of measuring the different degree of thermal expansion of various metals in the range where thermometers could not be used. Consisting of a brass clamp to hold metal rods, a burner to heat them, and a dial on a pillar, the instrument would demonstrate any changes in the bar's temperature, meaning any alteration in length would cause the steelyard to rotate, and the change registered on a scale. There is no other George Adams Senior pyrometer known to exist.

    See: Sally Newcomb's The World in a Crucible, 2009, p. 46.
    G.N. Cantor's Optics after Newton: Theories Of Light In Britain & Ireland 1704-1840, 1983

    Literature: This instrument is almost identical with the form of the instrument invented by the clock-maker John Ellicott and described by him in the 'Philosophical Transactions', xxxix 1736, pp. 297-99
Contacts
A fine and rare George Adams Senior pyrometer, English, Mid-18th century,
Auction information

This auction is now finished. If you are interested in consigning in future auctions, please contact the specialist department. If you have queries about lots purchased in this auction, please contact customer services.

Buyers' Obligations

ALL BIDDERS MUST AGREE THAT THEY HAVE READ AND UNDERSTOOD BONHAMS' CONDITIONS OF SALE AND AGREE TO BE BOUND BY THEM, AND AGREE TO PAY THE BUYER'S PREMIUM AND ANY OTHER CHARGES MENTIONED IN THE NOTICE TO BIDDERS. THIS AFFECTS THE BIDDERS LEGAL RIGHTS.

If you have any complaints or questions about the Conditions of Sale, please contact your nearest customer services team.

Buyers' Premium and Charges

For all Sales categories, buyer's premium excluding Cars, Motorbikes, Wine and Coin & Medal sales, will be as follows:

Buyer's Premium Rates
27.5% on the first £2,500 of the hammer price;
25% of the hammer price of amounts in excess of £2,500 up to and including £300,000;
20% of the hammer price of amounts in excess of £300,000 up to and including £3,000,000;
and 13.9% of the hammer price of any amounts in excess of £3,000,000.

VAT at the current rate of 20% will be added to the Buyer's Premium and charges excluding Artists Resale Right.

Payment Notices

For payment information please refer to the sale catalog.

Shipping Notices

For information and estimates on domestic and international shipping as well as export licenses please contact Bonhams Shipping Department.