Stock No. C1148



A good 2-day marine chronometer by Thomas Mercer, St. Albans c1943

  • A good 2-day marine chronometer in its original mahogany box, signed on the silvered dial Thomas Mercer Ltd St. Albans, England. 16442, and engraved with the Admiralty ‘broad arrow’.
  • The 2-tier mahogany chronometer box has a glass top and measures 7¼” x 7¼” x 6¾” high.
  • The chronometer is now complete with a Thomas Mercer outer deck box, the latter probably made in the 1960’s or 1970’s. Outer box size 9½” x 9¼ x 8¼ high.
  • The chronometer has subsidiary dials for seconds and state of wind with blued steel hour and minute hands.
  • The chronometer is complete with its original ratchet winding key.
  • The movement, with Earnshaw type spring detent escapement, is stamped 16442 and the number is repeated inside the bowl.
  • The underside of the bowl is engraved with a broad arrow and HS1 indicating that the chronometer was in British Government service. 
  • See Notes below for details of the history of this chronometer.

The Thomas Mercer business was founded in 1858 and was Britain’s last chronometer maker, finally closing in the late 20th century.


Additional photographs









This chronometer was purchased by the Admiralty on 2 February 1944, transferred to Liverpool on 4 April 1944, and issued to its first ship on 27 April 1944. The chronometer was sold by the government on 7 May 1969.

The Chronometer records at Greenwich show the chronometer’s career:

2 February 1944 purchased from Thomas Mercer
4 April 1944 sent to Liverpool
27 April 1944 issued to S.S. Fort Machault
29 November 1948 received from S.S. Mount Revelstoke Park
10 May 1949 sent to Thomas Mercer
19 September 1949 received from Thomas Mercer (work cost £3-0-0)
22 May 1951 issued to R.F.A. Wave Prince
1 October 1952 put ashore at Rosyth
10 November 1952 received from Rosyth
27 March 1953 sent to Thomas Mercer
20 October 1953 received from Thomas Mercer (work cost £5-10-0)
16 August 1954 issued to R.F.A. Green Ranger
22 February 1956 put ashore at Malta (reported as ‘erratic’)
20 July 1956 received from Malta
16 November 1956 issued to R.F.A. Wave Knight
24 December 1957 put ashore at Sheerness
7 January 1958 received from Sheerness
7 May 1969 Sold to Graus Antiques

The Ships

S.S. Fort Machault
The Fort Machault, a ‘Victory Freighter’ class vessel of 7160 tons was built by Burrard Dry Dock Company, North Vancouver, Canada and completed on 4 November 1943. She was originally owned by Wartime Merchant Shipping Ltd (a British Government company) and operated by Larringa Steam Ship Company of Liverpool.

The Fort Machault sailed with various wartime convoys and was sold to the Park Steamship Company of Montreal in 1946. The vessel ran aground and was wrecked in 1947.

S.S. Mount Revelstoke Park
The Mount Revelstoke Park, 7144 tons, was built by Marine Industries, Tracy, Quebec and completed on 31 July 1943 and operated by Mclean Kennedy Ltd of Montreal for the Canadian Government. The vessel was sold for scrap in 1967.

R.F.A. Wave Prince
Royal Fleet Auxiliary Wave Prince was built by J Laing & Sons, in Sunderland and launched on 27 July 1945. She entered service in March 1946 as a ‘replenishment oiler’. Between June 1950 and July 1953 the Wave Prince supported UN shipping during the Korean War. The vessel was broken up in 1966.

R.F.A. Green Ranger
The Green Ranger was built by Caledon in Dundee and launched on 22 August 1941. The vessel entered service as a ‘fleet attendant oiler’. The vessel ran aground when under tow in November 1962 and was lost.

R.F.A. Wave Knight
The Wave Knight was built by J Laing & Sons, in Sunderland and launched on 22 October 1945. She entered service in January 1947. The vessel was taken out of service in 1964 and broken up.


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