Display Watch

watch in the box
watch index 2
country British  
piece name (title): HP Isaac lever deck watch
plate three quarter
plate finish gilt
date 1892
case style open
case material silver
escapement lever
serial number 10859
maker Patrick Henry Isaac: Isaac made many forms of watches and experimented continuously. He made deck watches specifically from 1888-1896. Watchmaker to the British government, Indian and Colonial governments. his chronometer was used in the arctic Expeditions of 1875 and 1903.
movement Three-quarter plate, keyless, jeweled, going-barrel movement, with cap jewel on balance (diamond), straight line escapement and bimetallic balance with gold screws, free-sprung balance-spring with overcoil The plates are marked with the British Government property mark and also engraved, 'Henry P. Isaac, 10 Spencer street, London' and at the center of the plate, 'Maker to the Admiralty, No. 10859' (no.10850 deck watch was made in 1890 by Isaac). No decorative engraving to the movement.
escapement English (tangential) lever with ratchet tooth escape wheel.

Cut compensated bimetallic balance wheel with gold screws.

Free-sprung blue steel hairspring with overcoil and polished steel stud.
case A silver open face double back case with polished back cover and hinged cuvette, a hallmarked pendant, (possibly a later replacement), placed at the twelve position. The fluted crown gilt. (T he bow not present; these were often removed by the Admiralty in an attempt to make the watch less desirable as a personal timepiece and hence deter pilfering).

A base metal outer drum and bezel mounted in the wooden box protects the watch when in service.
case marks Leopard's head for the London Assay Office, lion passant for sterling silver (925/1000 purity), upper case "R" for 1892/3, "F.T" in an oval cartouche for Frederic Thoms at 200 Goswell Road, Clerkenwell, registered 4th October 1883, (cancelled 19th November 1892 due to change of address to 41 Spencer Street, Clerkenwell). Frederic Thoms was one of the most highly regarded watch case makers of his day, and succeeded to the business of the Thickbroom family around 1881.
dial and hands White enameled dial with Roman hour chapter, closed minute ring to the outside, English steel Spade hands, sunken subsidiary seconds dial at 6, and marked below the twelve with the broad tripartite arrow for British government property, 'Isaac, 10859'.

The blue steel spade hour and minute hands and the subsidiary seconds hand appear to be original.
notes Outer Box: The wooden protective box with outer drum and bezel mounted in the two part base, probably mahogany with some signs of restoration, with well-made brass catch and hinges.

The original mahogany box will enhance the value, as will the Admiralty pheon.

Chronometer: This is not a chronometer, but a high quality deck watch sold to The Admiralty, whose performance standards were very high.
valuation The condition of the watch, case and box are very good.

Achieved prices for similar watches by reputed makers, including this exact watch, have been found and form the basis of this valuation.

The valuation is $1600-2000.
copyright © 2017 Graham Morse and Martin Rosen
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