Quite honestly an entire book should be dedicated to dating a clock. Some time ago I published an article entitled, “How to Date an Antique or Vintage Clock – Part I”, and I used specific examples from my own collection.
I wanted to explore the topic a little further and this post will present a variety of methods used to date an antique or vintage mechanical clock.
There is no single method of dating an antique or vintage clock but there are some strong clues in some situations and subtle inferences in others that help determine when a clock was manufactured.
Occasionally, the exact month and year is displayed somewhere on the case, and in other instances the clock by way of serial numbers, date stamps on the movement, style of hands, spandrels, dial design, case design, and so on, establishes the date to within a certain period.
After 1896 foreign clocks (Europe, England) were mandated to have the country of origin on the case, usually on the dial. Any clock made after that date will have the country of origin.
How long a company was in business
A little research into the history of any clockmaker will put you in the right ballpark for dating your clock. For example, E.N. Welch, an American clock company made clocks up to 1903 when they were taken over by the Sessions Clock Company which made clocks up to 1970.
By 1903 Junghans was the largest clock manufacturer in the world and continued in its quest to bring more companies into the fold. Gustav Becker, founded in the 1860s and Hamburg American Clock company, founded in 1883 were absorbed by Junghans in the late 1920s. Although combined with Junghans in 1926 the Gustav Becker name lived on for another 9 years.
Steel vs brass plates vs wood
Smaller shelf clocks with 1-day (30 hour) wooden movements were produced in fairly large quantities from around 1810 to 1845, after which most clock makers changed over to brass movements. Wood dials were also popular during this period.
By 1860 iron weights were being replaced by springs as the power source, and smaller clocks, many of them 8-day, were becoming increasingly popular. Early American spring driven clocks used brass springs (late 1830s) until steel became cost effective.
During periods where brass was in short supply such as the World Wars (WWI and WWII), makers often made steel plate movements with brass bushing inserts. However, some companies such as Arthur Pequegnat used either steel plates or brass plated steel plates throughout their operating years (1902 to 1941).
Yet others used steel as a cost cutting move when the price of brass was high and not necessarily during the war periods.
Screws and nails, chime rods, coiled gongs
In older clocks nails and screws were made of iron and hand-forged, and screw heads were slotted. Hand forged nails are found in clock cases made from the earliest clocks through to the mid 19th century after which machined screws and nails began to be used.
An ogee clock as in this example made by George H. Clark in 1865 was constructed using hand forged nails.
Robertson and Phillips heads screws were introduced in the first part of the twentieth century. Since the Robertson head was invented in 1906 and Phillips screw heads only began to be widely used in the 1930s screws of these types found in older antique clocks are later additions.
The first rod gong (a single striking rod) goes back to DRGM 108469 by Johann Obergfell – granted on December 23rd, 1899. American rod gongs tend to be fairly crude in comparison. Rods are typically made of a copper or nickel alloy and press fit into the block.
There are two types of coils: the thick coils that spiral only a few times and give a great deep tone – and the smaller wire coils that spiral around many times and often have a thin tin-like tone. Thick coils were used much earlier than the mid 1800’s. The coils are usually mounted onto a fitting which is then mounted onto an iron block. Small thick coils became widespread towards the end of the 19th century.
On the American front, thin wire coils were popular. Some examples had the coil mounted to a dome shaped base which was said to improve the tone considerately.
Seth Thomas and others used ‘bell metal’ gongs in some of their clocks. These have a notably good tone compared to other American coiled gongs of the period.
Commemorative plaques which display dates are often a good indicator of the age of a clock. However, the clock may have been on a sellers shelf for years before the date on the plaque. This nevertheless places the clock within a certain range of dates. This photo shows a plaque on a HAC (Hamburg American Clock Co.) time and strike shelf clock.
Type of escapement
Recoil (anchor), half deadbeat, Graham deadbeat, pinwheel, Brocot types are found in older antique clocks while, hairspring, floating balance, lever type escapements are found in newer vintage (less than 100 years old) clocks.
For example, floating balance movements began appearing in mechanical clocks in the early 1950s. The floating balance will tolerate being out of level unlike pendulum clocks which must be on a level surface, an attractive marketing feature.
Style of case
Style of case such as ogee, box clock, steeple, cottage, gingerbread will place the the clock within a certain date.
For example the steeple clock is a simple Gothic revival design. Its origins can be traced to early 19th‐century English shelf clocks. The London model was in the form of a graceful pointed arch. In the late 1830s Americans had simplified the design to a triangular form with turret like finials. Steeple clocks were sold by many clock makers up until the 1890s.
Knowing when a case was made is a good indicator of its age. Although there are earlier patent dates stamped on the movement of this E. Ingraham Huron time and strike 8-day shelf clock, this style of case was made for only 2 years, 1878 to 1880.
Date stamps on movements or cases & searchable databases
Some makers stamps date their movements or display the date elsewhere on the clock case. The Gilbert Clock Company often date stamped their movements. Sessions put dates on the door labels.
Some makers such as Junghans stamp a date code on their movements. For example B19 stamped on the back plate of a Junghans movement refers to a movement made in the latter half of 1919.
Serial numbers stamped on movements can be compared to a database to determine the exact year the clock was made. The Ridgeway clock company used 4 digit codes. For example serial number 4981 refers to a Ridgeway clock made in 1981. Gustav Becker clocks were made in both Silesia and Braunau factories, both of which produced clocks but each had a unique serial number convention. The serial number on a Gustav Becker clock will give the exact year of production assuming you know where it was made.
An online databases such as ClockHistory.com provides invaluable information on companies and models made by them, the years the clock company was in business, and how long the company was in operation.
Searchable databases like Mikrolisk, the horological trademark index helps date a clock by comparing a trademark. Some companies revise or restyle their trademarks over the years allowing one to date a clock within a certain period.
At Antique-horology.org keywords or text can be used to search trademarks and identify years they were used.
The date 1848 is stated for the above clock. I arrived at the date because the clock was made by William McLachlan of Newton Stewart, Scotland. According to an English clock database Mr. McLachlan was an clock assembler and operated a clock-making business in Newton Stewart until his death in 1848. The clock could have been assembled as early as 10 years previously but 1848 is a conservative estimate.
Other miscellaneous indicators
Plywood began to be used in clock cases beginning in 1905. I have a Junghans bracket clock with a plywood back access door, made around 1913.
Adamantine clocks were most popular through to 1915. Seth Thomas made clocks in marble cases for a short time, from 1887 to about 1895. They also made clocks in iron cases finished in black enamel, from 1892 to about 1895.
But Seth Thomas is best known for their “Adamantine” black mantel clocks, which were made starting in 1882. Adamantine is a celluloid veneer, glued to the wood case. Adamantine veneer was made in black and white, and in coloured patterns such as wood grain, onyx and marble.
And there you have it. My objective was to give a broad generalized overview. Any one of the sub-topics above could be expanded at great length and I hope for some of you it becomes a helpful reference. I stand corrected on some of the dates and if there is anything amiss or other information I should have included, please leave a comment.
For some collectors and clock aficionados dating a clock is important, for others, not so much particularly if the clock is merely a decoration.
As I have outlined, there are many ways to date a clock, some are very obvious but as I said some are subtle while others takes a little research to determine the date plus knowing exactly where to look.