Tuesday, February 24, 2009

Was Peter Columbo a Clockmaker?

Probably not, but he would have probably been pretty good at clock restoration because oftentimes, restoring an antique clock in a historically correct manner not only requires a mandatory high level of technical skills and knowledge but also the intellectual curiosity, deductive reasoning and persistent "detective" work to understand, and faithfully recreate, the original clockmaker's design given the typical situation of incomplete information and more than a few missing parts.

Recently, I had the opportunity to acquire a rare, and very early (ca. 1876), Johann Baptist Beha Number 932 cuckoo and monk clock. This clock is rather unusual for a Beha clock in that it not only has time, strike and cuckoo complications but also an animation complication in which a monk comes out of the lower door three times a day to ring the Angelus (the monk's arm goes up and down while clock's two gongs are struck to simulate the ringing of a bell in the church's steeple). At ca. 35 inches tall, it is also one of the largest Beha clocks.

Production of these clocks were extremely limited, presumably due to the small market size resultant from the very high price of the clocks in terms of an average person's wage at the time.

The example I acquired is in remarkably good condition considering the fragility of the clock's steeples, etc. but the last ca. 140 years did take a bit of a toll: the crest above the cuckoo's door had been lost. In addition, the count wheel, which controls the timing of monk’s ringing the Angelus and the gear that drives this count wheel, was also missing.

Because of the generosity of time and information provided by fellow Black Forest clock collectors Mr. Mark Singleton, Mr. Dean Sarnell and Dr. Wilhelm Schneider (to all of which I am deeply indebted) and the photographs of a Beha 932 clock included in Rick Ortenburger's "Black Forest Clocks" it has been possible to determine the basic style and design of missing crest and Angelus count wheel and drive gear. Thus, restoring the missing crest and enabling the basic functions of the clock now appear rather straightforward. However, restoring the clock to basic function and restoring the clock to include the subtle design details it's makers' intended are not necessarily synonymous.

Upon inspection of the Angelus count wheel one notes the setting of pins that activate the Angelus ringing event. Closer inspection however reveals that, in addition to the two set pins, there are numerous other positions marked with small indentations on the outer diameter of the Angelus count wheel. Faithful reproduction of this count wheel would thus require replication of these features at the correct positions. But why are these non-functional (unpinned) positions present and what is the horological logic of their pattern? More practically, how can one precisely replicate a pattern if one can't recognize the pattern? To me, at least, the answers to both questions are not obvious and require a bit of detective work...

In cooperation with my good friend, Dr. Martin Wolk, we have been trying to analyze and understand the design logic behind the marked horological positions on the Angelus count wheel. While we are not ready to yet declare success I think we have perhaps gained some insight and have developed an initial hypothesis (theory) that must now be tested through critical analysis and peer review. Our basic hypothesis is that, in the cottage Black Forest clock industry of the mid- to late-nineteenth century, there may have been an attempt to gain economies of scale in manufacturing by fabricating clock parts that could be used in multiple applications and clocks. Accordingly, the pattern of these indentations in the Angelus count wheel might represent a series of pre-registered positions that could be drilled, and pinned, to create a wide range of time intervals over which horological-registered events (i.e. a monk ringing the Angelus, a music box playing, etc.) could be activated. Thus, a "standard" count wheel could be customized via the setting of pin positions to fabricate a multiplicity of different clocks.

According to our current hypothesis, if one lets x represent the smallest interval between two consecutive marked positions on the Angelus count wheel, it appears that there are two intervals with 1x spacing, eight intervals with a 2x spacing, six intervals with a 3x spacing and six intervals with a 4x spacing. Thus, there are a total of 60x intervals (2*1x + 8*2X + 6*3x + 6*4x) about the circumference of the Angelus count wheel. Since there are sixty teeth on the Angelus count wheel and the Angelus count wheel rotates once every 24 hours, each x interval must then correspond to 0.40 hours or 24 minutes. Thus the intervals defined by successive markings on the Angelus count wheel would correspond to 0.40 hours (for each of the 1x intervals), 0.80 hours (for each of the 2x intervals), 1.20 hours (for each of the 3x intervals) and 1.60 hours (for each of the 4x intervals). Starting from position 1 and moving counter-clockwise, the interval sequence (in hours) is approximately …0.8, 0.8, 08, 0.4, 0.8,1.6,1.6, 1.6, 1.2, 1.2, 1.2, 0.8, 0.8, 0.8, 0.4, 0.8, 1.6, 1.6, 1.6, 1.2, 1.2, 1.2…

Given this sequence, pins may then set via combinations and permutations to create all of the following time intervals (in hours): 0.40, 0.80, 1.20, 1.60, 2.00, 2.40, 2.80, 3.20, 3.60, 4.00, 4.40, 4.80, 5.20, 5.60, 6.00, 6.40, 6.80, 7.20, 7.60, 8.00, 8.40, 8.80, 9.20, 9.60, 10.00, 10.40,10.80, 11.20, 11.60, 12.00, 12.40, 12.80, 13.20, 13.60, 14.00, 14.40, 14.80, 15.20, 15.60, 16.00, 16.40, 16.80, 17.20, 17.60, 18.00, 18.80, 19.20, 19.60, 20.00, 20.40, 20.80, 21.20, 21.60, 22.00, 22.40, 22.80, 23.20, 23.60, 24.00. Additional flexibility in these intervals could obviously be gained by modifying the rotation frequency of this count wheel.

Clearly, this sequence of pre-registered positions on the count wheel would have provided the nineteenth century Black Forest clockmaker with a wide range of closely spaced time intervals for customizing animation, music, and other events registered to time.

As I indicated above, this is only our initial hypothesis and elucidation of the true significance and function of the non-functional marked positions on the Beha 932’s count wheel is a work in progress….I'll update the blog as we get smarter :-)

Comments and alternate theories are welcomed!

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