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Guidance in making write-ups (descriptions) of a chronometer for those whose native language is not English.

 

CHRONEMETERS

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Click either the red numbers on the pictures or an index item below.

Case
Dial
Movement
Handles
Hands
Maker
Escutcheon

 

Basic aspects of a description

Inspiring descriptions

 

  Drop handles. Tier 1 of a 3-tier box. Tier 2 of a 3-tier box. Tier 3 of a 3-tier box. Brass box boundings. Key escutcheon Bone plaque (with signature) State of wind indicator. Up/Down indicator. Seconds chapter and seconds hand. Hour and minute chapter. Gimbal ring. Gimbal locking screw and tongue. Ratchet key.

Helical balance spring. Timing nut. Balance weight. Bi-metallic compensating balance. Auxiliary compensation. Spotted (barrel bridge) plate. Balance cock endstone.

Guard box.

     
 
 

 

Subjects   Possible 'write up’s'
  Case The whole is contained in a nicely colored three tier mahogany box with campaign style handles. Size 7.75in high x 7.25in square.

supported on gimbals and housed in its original mahogany brass bound, two tier box with drop handles.

Gimbaled brass tub in a three tier brass bound mahogany box.

Locking brass reinforced box.

the spring-detent movement gimballed within the brass bound rosewood three tiered case. 8 ins square case. Number 3511.

the brass bound mahogany box in very untouched condition.

The rosewood brass inlaid box is numbered and of excellent colour and patination.

Three tiered box. Numbers on box, dial, movement and bowl all match.

A mahogany boxed 2 day marine chronometer.

...in triple mahogany brass bound box.

chronometer in an ebony and brass strung box, with mahogany outer guard box

The 3-tier ebony box with brass stringing, brass key escutcheon and brass plaque to the upper lid has flush brass handles and a bone plaque signed D. McGregor....

15) The outer mahogany guard box with horsehair packing (re-covered) has a leather strap (repaired) and measures 9½" x 9½" x 9¼" high.

 

Dial The silvered engraved dial with black lettering includes chapters for both the hour and seconds and an up/down indicator.

Silvered dial with wind indicator and sub seconds engraved A. Johannsen & Co.

Exceptionally clean dial.

 subsidiary dials for seconds and state of wind

  Escutcheons brass key escutcheon and brass plaque to the upper lid
  Handles Recessed handles.

two tier box with drop handles.

has flush brass handles

Hands  ..finely made gold hands.

..and gold hour and minute hands.

..blued hands.
 

Maker

engraved A. Johannsen & Co. Makers to the Admiralty, Indian government and Royal Navies of Italy, Spain and Portugal. 149 Minories London 8275.

 the dial signed D. McGregor & Co Makers to the Admiralty, Glasgow & Greenock M/1983

 this is the serial number of Thomas Mercer who made this instrument, McGregor's being the retailer. Mercer records show that chronometer number 1983 was sold to McGregor in 1871.

 and a bone plaque signed D. McGregor & Co Makers to the Admiralty Glasgow & Greenock.

Chronometers by Parkinson & Frodsham are considered to be of the finest workmanship. Circa 1815.

Movement The gimbaled movement, possibly by Mercer, remains in its original bowl and contains all the requisite parts including its original detent escapement, a chain fusee, maintaining power, a helical palladium hairspring and a bimetallic compensating balance wheel.

Earnshaw detent escapement, spotted plates, keywind, keyset, serial number 8,275.

..the spring-detent movement gimballed within the brass bound rosewood three tiered case.

A fine 2 day Marine chronometer with spring detent escapement.

...2 day marine chronometer with Earnshaw type detent escapement and Poole's auxilary compensation.

no.3939 with auxilary compensation and Earnshaw type detent escapement,

Earnshaw type detant escapement and auxilary compensation with finely spotted plates.

... with the escapement mounted on a separate platform adjacent the fusee and mainspring barrel. Blued free sprung helical balance spring. Spring detent bi-metallic balance with blued rims and trapezoidal (wedge shaped) weights.

... a two arm bi-metallic balance with two wedge-shaped weights and a blue steel free-sprung helical balance spring. The escapement is a spring detent of the Earnshaw type.

The mainspring is signed and dated:
"John Mills, September 26, 1829,

 

 

   

Basic aspects
of a simple description

Sample text
Title:
 quality/status, style, type, maker, place, date.
  A fine 2 day marine chronometer by Mc. Gregor Glasgow no.3939. ca 1850
Case:
 quality, type, design particulars, material, components and ornaments.
  The 3-tier  brass bound mahogany case of excellent colour and patination with brass key escutcheon, brass plaque to the upper lid, flush brass handles and a bone plaque signed D. McGregor & Co Makers to the Admiralty Glasgow & Greenock.
 
Dial:
 quality, type, material, features, components, ornaments.
  The silvered engraved dial with black lettering includes chapters for both the hour and seconds and an up/down indicator is signed D. McGregor & Co Makers to the Admiralty Glasgow & Greenock no.3939.
Movement:
 quality, duration, material, construction, escapement, striking repeating musical features.
  The gimbaled movement, possibly by Mercer, remains in its original bowl and contains all the requisite parts including its original Earnshaw type detent escapement, a chain fusee, maintaining power, a helical palladium balance-spring and a bimetallic compensating balance wheel.
Maker or origine:
give as much information as possible on the maker and or region of manufacturing.
  D. McGregor & Co are recorded as makers to the Admiralty Glasgow & Greenock ca 1850, and retailers of Thomas Mercer. 
Dimensions:
 H= height
W= width
D= depth
L= length
Diam= diameter
 
Size 7.75in high x 7.25in square.
Literature (acknowledgements):
 state where similar objects are described or exhibited, and the source of the makers biographical particulars.
 
Lit: Brian Loomes, Watchmakers and Clockmakers of the World. Volume 2. NAG press Ltd London.

Tip:
Be careful when using 'promotional' terms
 

Like: most imposing, attractive, well executed, good, fine, very fine, impressive, well proportioned, fine quality, extremely rare, important, beautifully executed, extraordinary, outstanding,
 

 

 

 

 

   

Sample descriptions.

 
   
  The chronometer has a good quality movement, subsidiary dials for seconds and state of wind, and gold hour and minute hands.
  The movement is supported on gimbals and housed in its original mahogany brass bound, two tier box with drop handles. Chronometers by Parkinson & Frodsham are considered to be of the finest workmanship. Circa 1815.
  A mahogany boxed 2 day marine chronometer with Earnshaw type detent escapement and Poole's auxilary compensation.
 
  A fine and impressive 8 day mahogany chronometer by John Fletcher no.3939 with auxilary compensation and Earnshaw type detent escapement, having been on a sailing yacht the Silvia around 1925.
 
  Model 22 Hamilton Marine Chronometer with wind indicator and subsidiary constant seconds register. Clean metallic dial. Base metal large case fully marked for the U.S. Navy BU Ships 1941. 21 jewel movement also bears U.S. Navy BU Ships legend.
  A very good 2 day marine chronometer with original spring detent escapement. The rosewood brass inlaid box is numbered and of excellent colour and patination.
  The chronometer has the serial number 1850 internally on the back of dial, on the front plate and on the underside of the balance cock; this is the serial number of Thomas Mercer who made this instrument, McGregor's being the retailer. Mercer records show that chronometer number 1983 was sold to McGregor in 1871.
  Marine Chronometer by Kelvin & Wilfred O. White, New York & Boston. No. 15521 CA1943. Three tiered box. Numbers on box, dial, movement and bowl all match. Very good condition. Mercer mechanism ( as usual) . Exceptionally clean dial. Recessed handles. Overhauled by highly reputed repairman.
  A fine 2 day chronometer by this famous London maker with Earnshaw type detent escapement and auxilary compensation with finely spotted plates in triple mahogany brass bound box.
  An early example of an English 8 - day chronometer with the escapement mounted on a separate platform adjacent the fusee and mainspring barrel. Free sprung with blued helical spring, spring detent, bi-metallic balance with blued rims and trapezoidal weights. Silvered dial with winding indicator at 6 o’clock, finely made gold hands, gimbal mounted in a brass bowl that retains most of its original lacquer.
  A two-day marine chronometer in an ebony and brass strung box, with mahogany outer deck box, the dial signed D. McGregor & Co Makers to the Admiralty, Glasgow & Greenock M/1983
 
  A fine 2 day Marine chronometer with spring detent escapement, the brass bound mahogany box in very untouched condition.
 
  Johannsen 130 mm 10 jewel marine chronometer, ca. 1918, Earnshaw detent escapement, spotted plates, keywind, keyset, serial number 8,275. Silvered dial with wind indicator and sub seconds engraved A. Johannsen & Co. Makers to the Admiralty, Indian government and Royal Navies of Italy, Spain and Portugal. 149 Minories London 8275. Gimbaled brass tub in 3 tier brass bound mahogany box.
  A good quality 8-day marine chronometer, the spring-detent movement gimballed within the brass bound rosewood three tiered case. 8 ins square case. Number 3511.
  A traditional two-day marine chronometer signed on the dial by the maker TS & JD Negus, No. 2151. The silvered engraved dial with black lettering includes chapters for both the hour and seconds and an up/down indicator. The gimbaled movement, possibly by Mercer, remains in its original tub and contains all the requisite parts including its original detent escapement, a chain fusee, maintaining power, a helical palladium hairspring and a bimetallic compensating balance wheel. The whole is contained in a nicely colored three tier mahogany box with campaign style handles. Size 7.75in high x 7.25in square.
 
Election 80 mm flat cased deck watch, 17 jewel lever escapement with hack feature and counter rotating up down mechanism, stewind, pendent set, open face, serial number 524,688, ca. 1916. Engraved silver dial with wind indication disk signed Chronometre Election Grand Prix Bern 1914. Locking brass reinforced box.
 
Arnold's marine chronometer
the movement signed "John R. Arnold, London, invt et fecit No. 229,"the dial signed "Arnold / London / No. 229," the mainspring signed "R. Clark, 1797", the wooden tub with paper label "Decr 12th 1804," the reverse of the dial with scratched instructions to the dial engraver and with further scratched repair inscription "J R Sept 12 1816", and dates (?) 1792, 1804.
[dial: 8.15 cm. diam.; backplate: 6.45 cm. diam.]

The one-day gilt movement with pinned cylindrical pillars, fusee and chain, blued set-up ratchet and pawl on the separate barrel bridge, Arnold's spring detent planted on the backplate and visible in cut out, depth adjustment screw also in plate, brass escape wheel, free sprung bi-metallic Z-balance with shaped gold weights and gold cylindrical mean time screws, blued helical spring secured to steel plate on balance cock, escape wheel and second wheel jewels each set in chaton, silvered brass dial with roman chapters, subsidiary seconds ring, blued hands, within a mahogany tub with hinged silver bezel.

Recorded in Hans Staeger. 100 Years of Precision Timekeepers.

Not found in Greenwich Observatory's International Chronometer Index.

Condition: This example is extraordinary in its originality. Unlike most chronometers of this date that saw long years of service, it was never "modernized". The original parts were, in almost all cases, repaired, not replaced. The escapement retains its all the original components with the possible exception of the helical balance spring. The original escape wheel survives with a single tooth replaced. The hour and minute hands are original; the seconds hand is new.

The wooden tub and bezel are original, but there are plugged holes in the sides where it was once gimbaled. The turned base is new. Based on the dated mainsprings listed below, the most reliable date for the chronometer itself seems to be the paper label in the tub. The mainspring suggests that construction may have started earlier, during the lifetime of John Arnold (d. 1799).