Before timegraphers

May 9, 2021
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Back in the day, before electronic timegraphers, how did manufacturers and watchmakers measure beat error, amplitude, and such? Heck, how did the railroads measure the accuracy of the railroad grade pocket watches every week or month? Just well calibrated ears and eyes? I've searched a bit and haven't found anything on how they did it back in the day.
 

whizzer

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Mar 18, 2008
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Back in the day, before electronic timegraphers, how did manufacturers and watchmakers measure beat error, amplitude, and such? Heck, how did the railroads measure the accuracy of the railroad grade pocket watches every week or month? Just well calibrated ears and eyes? I've searched a bit and haven't found anything on how they did it back in the day.
Don't know for sure but based on my experience working on a survey crew some 70 odd years ago, they probably used a master clock adjusted periodically to sidereal time. If you know where you are on Earth you can determine the exact time by measuring the angle from your location to the North Star, then using the tables in a Solar Ephemeris to find the time. That's a very simplified explanation.
 

DeweyC

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Back in the day, before electronic timegraphers, how did manufacturers and watchmakers measure beat error, amplitude, and such? Heck, how did the railroads measure the accuracy of the railroad grade pocket watches every week or month? Just well calibrated ears and eyes? I've searched a bit and haven't found anything on how they did it back in the day.
Some factories had an astronomical observatory. Many others "bought" astronomical services from a local observatory. By 1870, time ticks were available from USNO by telegraph. In 1856 the President of Erie had a chronometer on his desk used to send the tick out to his departments

Chronometer makers, being intimately familiar with celestial navigation and instruments, also provided time services. For example the noon Time Ball in major harbors.

The distribution of time is a very interesting piece of history. I think (?) one good book written in the 1930s is Time Matters or something like that. It described the vaults in the USNO basement where the Reifler regulators were mounted.


 

John Runciman

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manufacturers and watchmakers measure beat error, amplitude, and such
amplitude is easy that's a visual observation.

there are people that can hear if the watches out of beat. Otherwise it's more of a visually making sure everything looks like where it's supposed to be.then I'm doing things slightly out of order as a reference to the book below and after I got the book I looked at this question is answered on page 122.

The rate depends upon who is doing the observations. It also depends upon how far you want to go back? the simplistic answer is a watch is compared to another timepiece of greater accuracy. in the case of a watch shop they could have a regulator clock or as someone pointed out above they could have a chronometer. Which is nice because that could be taken to someplace where they have a master clock synchronized to stars.

chronometer certification was a little bit different same thing you're comparing to a master clock like a regulator. They would usually have two people one person to look at the watch the other person to look at the regulator. two people make it a lot easier when you're writing numbers down.

another way that they did chronometer certification was with the recording chronograph? Fortunately I don't have to describe how that works I found a reference to a book for you plus there's all kinds a bonus information on how they did it before timing machines. page 78 talks about the recording chronograph. This meant they only needed one person to do the observing versus two people. then I believe the recording chronograph is much more accurate then two people working timepieces. The next page continues on ideas for how to time your watch. Then jump ahead the page 158 towards the bottom the reference to buying the best quality regulator you can afford. I think you'll find the book is filled with all kinds and answers to questions you haven't even thought of yet.

The watch adjuster's manual [microform] : being a practical guide for the watch and chronometer adjuster in making, springing, timing and adjusting for isochronism, positions and temperatures : Fritts, Charles Edgar : Free Download, Borrow, and Streaming : Internet Archive
 

DeweyC

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Some factories had an astronomical observatory. Many others "bought" astronomical services from a local observatory. By 1870, time ticks were available from USNO by telegraph. In 1856 the President of Erie had a chronometer on his desk used to send the tick out to his departments

Chronometer makers, being intimately familiar with celestial navigation and instruments, also provided time services. For example the noon Time Ball in major harbors.

The distribution of time is a very interesting piece of history. I think (?) one good book written in the 1930s is Time Matters or something like that. It described the vaults in the USNO basement where the Reifler regulators were mounted.
OK. "Time Matters" which is really "Matter of Time" is not the book I was thinking of. But it is a very good survey of the history of time and devotes two chapters to Gruen. Published 1947.

The book I was reaching for is Milham's "Time and Timekeepers" which provides a great description of the role of the USNO. Published 1923.
 

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