The Grandfather Clock

The grandfather clock (also a longcase clock, tall-case clock, grandfather’s clock, or floor clock) is a tall, freestanding, weight-driven pendulum clock with the pendulum held inside the trunk or waist of the case.

Clocks of this style are commonly 1.8–2.4 metres (6–8 feet) tall. The case often features elaborately carved ornamentation or fretwork on the hood (or bonnet), which surrounds and frames the dial, or clock face.

The English clockmaker William Clement is credited with the development of this form of clock case in 1670 and until the early 20th century, pendulum clocks were the world’s most accurate timekeeping technology, and longcase clocks, due to their superior accuracy, served as time standards for households and businesses.

Today they are kept mainly for their decorative and antique value, having been widely replaced by both analog and digital timekeeping.

Lateral view of a longcase clock movement without a striking mechanism, mid-1800s.

Longcase origin comes from Horological development.

The advent of the longcase clock is due to the invention of the anchor escapement mechanism by Robert Hooke around 1658. Prior to the adoption of the anchor mechanism, pendulum clock movements used an older verge escapement mechanism, which required very wide pendulum swings of about 80–100° Long pendulums with such wide swings could not be fitted within a case, so most freestanding clocks had short pendulums.

The anchor mechanism reduced the pendulum’s swing to around 4° to 6°, allowing clockmakers to use longer pendulums, which had slower “beats”. These consumed less power allowing clocks to run longer between windings, caused less friction and wear in the movement, and were more accurate. Almost all longcase clocks use a seconds pendulum (also called a “Royal” pendulum) meaning that each swing (or half-period) takes one second.

These are about a meter (39 inches) long (to the center of the bob), requiring a long narrow case. The long narrow case actually predated the anchor escapement clock by a few decades, appearing in clocks in 1660 to allow a long drop for the powering weights.

Lateral view of a Timothy Mason longcase clock movement with striking mechanism, circa 1730

However, once the seconds pendulum began to be used, this long weight case proved perfect to house it as well.

British clockmaker William Clement, who disputed credit for the anchor escapement with Robert Hooke, made the first longcase clocks by 1680. Later the same year, Thomas Tompion, the most prominent British clockmaker, was making them too. Longcase clocks spread rapidly from England to other European countries and Asia.

Between 1680 and 1800, the average price of a grandfather clock in England remained steady at £1 10s. In 1680, this was the amount paid by an average working family for a year’s rent, so the purchase of clocks was confined to the relatively well-off. But by 1800 wages had increased enough so that many lower middle-class households owned grandfather clocks.

Modern longcase clocks use a more accurate variation of the anchor escapement called the deadbeat escapement.

Description of weights and movements.

Traditionally, longcase clocks were made with two types of movement: eight-day and one-day (30-hour) movements. A clock with an eight-day movement required winding only once a week, while generally less expensive 30-hour clocks had to be wound every day.

Eight-day clocks are often driven by two weights, one driving the pendulum and the other the striking mechanism, which usually consisted of a bell or chimes. Such movements usually have two keyholes, one on each side of the dial to wind each one.

By contrast, 30-hour clocks often had a single weight to drive both the timekeeping and striking mechanisms. Some 30-hour clocks were made with false keyholes, for customers who wished that guests to their home would think that the household was able to afford the more expensive eight-day clock.All modern striking longcase clocks have eight-day mechanical quarter chiming and full hour striking movements. Most longcase clocks are cable-driven, meaning that the weights are suspended by cables. If the cable were attached directly to the weight, the load would cause rotation and untwist the cable strands, so the cable wraps around a pulley mounted to the top of each weight. The mechanical advantage of this arrangement also doubles the running time allowed by a given weight drop.

Cable clocks are wound by inserting a special crank (called a “key”) into holes in the clock’s face and turning it. Others, however, are chain-driven, meaning that the weights are suspended by chains that wrap around gears in the clock’s movement, with the other end of the chain hanging down next to the weight. To wind a chain-driven longcase clock, one pulls on the end of each chain, lifting the weights until the weights come up to just under the clock’s face.

Elaborate striking sequences

In the early 20th century, quarter-hour chime sequences were added to longcase clocks. At the top of each hour, the full chime sequence sounds, immediately followed by the hour strike. At 15 minutes after each hour, 1/4 of the chime sequence plays, at the bottom of each hour, 1/2 of the chime sequence plays, and at 15 minutes before each hour, 3/4 of the chime sequence plays.

The chime tune used in almost all longcase clocks is Westminster Quarters. Many also offer the option of Whittington chimes or St. Michael’s chimes, selectable by a switch mounted on the right side of the dial, which also allows one to silence the chimes if desired. As a result of adding chime sequences, all modern mechanical longcase clocks have three weights instead of just two. The left weight provides power for the hour strike, the middle weight provides power for the clock’s pendulum and general timekeeping functions, while the right weight provides power for the quarter-hour chime sequences.

The Origins of the Grandfather Clock’s name.

The Oxford English Dictionary states that the popular 1876 song My Grandfather’s Clock is responsible for the common name “grandfather clock” being applied to the longcase clock.

The song was composed by an American songwriter by the name of Henry Clay Work who discovered a long grandfather clock in The George Hotel in Piercebridge, in County Durham in England. When he asked about the clock, he was informed that it had two owners. After the first owner died the clock became inaccurate and when the second owner died, the clock stopped working altogether. The story inspired Henry to create the song.

Pot bellied French Comtoise clocks.

Comtoise clock

Comtoise clocks, also known as Morbier clocks or Morez clocks, are a style of longcase clock made in the French region Franche-Comté (hence their name). Features distinguishing this style are a curving “potbellied” case and greater use of curved lines. Often a heavy, elongated, highly ornamented pendulum bob extends up the case.

Production of these clocks began in 1680 and continued for a period of about 230 years. During the peak production years (1850–1890) over 60,000 clocks were made each year. These clocks were very popular across the generations, and they kept the time on farms throughout France. Many Comtoise clocks can be found in France but they are also frequently found in Spain, Germany, and other parts of Europe, unfortunately, less in the United States and the UK.

Many Comtoise clocks were also exported to other countries in Europe and even further, to the Ottoman Empire and as far as Thailand. The metal mechanism was usually protected by a wooden sheath.

The Danish Bornholm clocks.

Bornholm clock made by Edvart Sonne

Bornholm clocks are Danish longcase clocks and were made on Bornholm from 1745 to 1900. In Sweden, a special variety of longcase clocks was made in Mora, called Mora clocks.

According to the Bornholms Museum, the story behind the famous Grandfather Clock (in Danish: Bornholmerure) begins with a shipwreck. In 1744 a Dutch ship ran aground between Rønne and Hasle with English grandfather clocks in the cargo. Local craftsmen, who knew how to tool wood, had the best prerequisites to work with smaller mechanics and was therefore put on the task to clean and repair the clocks before they were sent to salvage auction.

After working with the Grandfather Clocks, the craftsmen were motivated to manufacture clocks themselves and suddenly a production and export of Clocks from Bornholm were started. The clocks were partially sold to local market towns and farms and partially exported to the rest of Denmark. Eight craftsmen became the first self-taught watchmakers, among these the two brothers Otto and Peter Arboe are well-known.

For more information on these beautiful Bornholm clocks visit the Bornholms Museum

Swedish Mora Grandfather Clock.

A Mora clock dating from 1834, with later painting on the case

Mora clocks were made from the late 1700s to about 1850, initially around the area of Mora in Sweden’s central Dalarna region. In the mid-1700s, when the agriculture and mining industries were facing a downturn, a cooperative of families in Mora, took up clock-making to supplement their meager incomes. Production began in the late 18th century and continued through most of the 19th finally succumbing to the increased competition from newer styles and cheaper mass-production methods.

Mora clock faces are often marked with the inscription “A A S Mora”—the initials of Krång Anders Andersson (1727-1799) of Östnor, traditionally known as the first clockmaker in the district of Mora. The discovery of his initials on a clock movement dated 1792 has been taken as evidence that the cottage clock industry was already flourishing by this time.

This cooperative manufacture of clocks in Mora arose as a source of supplemental income for the farm families of this agriculturally poor region. Each family would “specialise” by making one or more of the parts required. A finished clock would often be sold without a case—the buyer then arranging for one to be made, often locally. This helps to explain the great variety of cases that exist.

Regional differences exist within Sweden as to the styles of Mora Clocks made. The style of Mora Clocks made in the North of Sweden though featuring the same basic shape differed quite markedly from those Mora Clocks made in the South of Sweden.

Gunnar Pipping has estimated that more than 50,000 Mora clock mechanisms were made throughout the 19th century. At the peak period of their production, as many as 1,000 clocks were being made each year. Within 80 years, however, competition from inexpensive German and American clocks helped put an end to this cottage industry. The clocks have eight-day movements and strike the hours on two bells mounted above the clock mechanism or alternatively on a spiral wire gong. The weights were made of cast iron.