On many German antique pendulum driven clocks you will find several numbers on the back plate. For an explanation I refer to a Mauthe time and strike movement.

In the lower portion of the back plate you will see a series of numbers. Some of these numbers have a clear explanation while others are somewhat of a mystery. For example, the number 34 refers to the measurement in centimeters from the top of the suspension spring post to the bottom of the pendulum regulating nut.

Nomenclature of a German pendulum assembly

The 34 cm measurement includes the following: the very top of the suspension spring post, the suspension spring, pendulum hanger and pendulum rod and bob. Within the total length is the suspension spring which, for this movement is 2 centimeters in length. The pendulum rod from the hook to the bottom of the rod is 26.5 cms.

The figure 116 adjacent to the 34 number on the movement refers to beats per minute.

Heinrich Kielmann patented hanger

The number 55006 is a patent number. This patent was issued to Heinrich Kielmann (Ruhrort/Rhein) in 1890 or 1891 and concerned the hanging of the pendulum. However, Kielmann not only manufactured loose movements for other manufacturers to use but also allowed other makers to manufacture their own movements using his patented pendulum hanging system, which is why movements from other makers have this patent number stamped on them.

You might also find yet another number.

The number 7137 is a mystery

In the example above the number 7137 may refer to a production number or some form of coded method of expressing the date. As there is no known public database of Mauthe clocks, the last number is a mystery.

Should you happen to receive a movement without a pendulum rod or bob or even a case, the measurements can be helpful in securing replacement parts. Otherwise, knowing these numbers will certainly expand your knowledge of clock collecting and repair.