Look what I found for $50 USd; off topic but I think you will like the photos.


Hello all,

Been away from the computer for awhile here. No new HP calcs other then the 30b prototype to play with and 5 upgraded HP42s's.

Renovating the house, working, family, the book and now my 1973 Celica is going undergoing a ground up restoration. Bought it in 1974 in High School and it does not have a sticky accelerator pedal!

In any case all the business doesn't stop one from looking around and now to the off-topic topic:

Found this Scientific instrument at the local junk store for $50 USd. A Barograph circa 1940! Fully functional with spare barograph paper, used papers, working eight day clock, key, ink bottle, and spare nib. Now another project for restoration!

Here are the befores which will be followed at a later date with the afters:

Here is the Barograph as found with masking tape holding all the top 5 panel glass case together. The glass is all heavy plate glass and the cabinet is mahogany:

Another view with the two section drawer slightly open exposing a recorded chart labelled "Kaohsiung to Vancouver, B.C." Other charts include "Tokyo to Vancouver" and "Vancouver to Keelung". Obviously this was part of a ships meterology room!

This view is with the glass top removed:

A numbered explanation of the major components:

1  ink bottle
2 chart canister and clock mechanism within
3 11 diaphramed stack
4 the adjusting knob to synchronize the reading to a base
5 system of levers to transfer and amplify the pressure change
from the stack to the pen and chart
6 lever for retracting the pen arm from the chart cannister
7 the pen arm and nib, this one is corroded and non functional,
but replacement has been secured
8 the two section drawer containing used and unused charts.

The following shots are around the barograph with the top case removed and the lid and chart removed from the chart canister:


front quarter left:

rear quarter right:

rear quarter left:

edge on from lever side:

By removing the top lid from the chart canister one exposes the winding key and fast slow adjust:

Removing the centre screw knob in the above picture allows the entire canister containing the clock to be removed:

Continuing with the disassembly, eight tiny screws in the side of the canister exposes the clock mechanism gears and platform escapement:

I have placed the clock mechanism without canister back on to the base for ease of storage:

The inscription on the clock mechanism:

The inscription on the brass base plate:

Well there you have it, another project which will require the following:

1  case restoration and finish
2 brass strip, clean and relaqueur
3 new pen nib and correct ink
4 new charts
5 clock mechanism cleaned, adjusted and oiled.

I will do the work here and if your interested I will post the results. Of course this is for free time between writing the book (almost done), home, work, car, dog, life...

If you want more info on barographs start with wikipedia:

wikipedia barograph link

for parts if you have one:

parts link

The above link to the parts supplier is incredible, I already ordered new ink, charts, nib and the book and it arrived from England in 5 days!

Cheers, Geoff

Edited: 31 Jan 2010, 11:57 p.m. after one or more responses were posted


Hi, Geoff;

I did not only like the photos, I also liked to see the instrument itself. I always tell my students that knowing the destiny does not mean knowing the path, or, in terms of knowledge and technology, knowing current, updated technology does not mean knowing technology itself, one must know the path, the history, the origin. All digital versions of analog devices are only possible after mastering the physical phenomenon they deal with.

A beautiful instrument, indeed! I like it!

Thanks for sharing!

Luiz (Brazil)



Thanks for the response. I have two nephews, one an engineer and neither of them recognize pre 1980.

The engineer is a computer programming professional with an Engineering degree, electrical major and I tried showing him my functioning 9825A.

Chuckled at how primitive it was. Not the response I was expecting as these are the progenitors to his sophisticated systems. Also tried to explain (I taught courses at University during my post-grad studies) that the tech of today is the unsophisticated primitive of the future.

It may start to sink in....

Cheers, Geoff

Edited: 1 Feb 2010, 2:09 a.m.


That's a beautiful instrument Geoff. Like others, I look forward to any news you may post on the restoration.

Regarding your nephew, he shouldn't discount the early technology. There's a lot he can learn from it. I know because I'm also a computer programmer with an electrical engineering degree. People have lost sight of how fast computers are today and I have occasionally taken on projects at work that others thought couldn't be solved in a realistic amount of time. Knowing the basics of computers can help one write stunningly fast software. After all, a quad-core PC running at 3GHz executes a little less than 12 billion instructions per second. You can get a lot done in 12 billion steps... :)


As a collector of clocks and watches, that is a higher-grade movement than I would have expected.



Hello Tim,

I agree, nice high grade 11 jewel movement. The balance spring is elinvar with a non compensated balance. Interestingly the standard for an eight day barograph is a one hour deviation at the end of the period. When you consider one rotation of the barrel is 7 days then an extremely accurate clock is not a requirement as it would not be indicated by the scale of the chart.

The movement is standard 18000 beats per hour (5 beats per second) or 2.5 herz. With my vibrometer I will adjust this to within minutes per week as long as the temperature does not deviate to much in the house and that should not be a problem.

Over 40 clocks reside here, most American eight day ranging from 1812 to 1900.

Two hundred and fifty watches, 150 restored Omegas, Longines, Mido, Universal, Wakmann-Breitling, and others including the HP-01.

Here is a restored Georgian Bracket (ca 1812) clock I did a couple of years ago that you would be interested in:

and some of the watches:

Cheers, Geoff

Edited: 1 Feb 2010, 2:10 a.m. after one or more responses were posted


And nice to see some LED watches represented.

I don't have a good group shot, but here are a few highlights.

Omega Constellation 751, originally owned by my grandfather.

Waltham Colonial Riverside

And by far my most accurate watch (narrowly beating out my Bulova Accutrons) is this Hamilton 4992b.


Hello Geoff,

I have seen you restoring a few abused watches to mint (or very good) condition. Dumb question: how can you tell a worthy restoring project from an abused beyond repair item? Is it always possible to turn an ugly duckling into a swan?

Just curiosity.



Hello Juan

Most if not all of my collection are museum restorations. I pay particular attention to finding new-old-stock parts whenever possible.

Before on the right, after on the left (hopefully that was obvious)! The dial was redone, the hands stripped, relumed and painted, crystal polished with diamond polishing paste, movement cleaned, lubricated and timed, case finish redone in the brushed sunburst pattern. All the gaskets in crown, pushers and case were replaced.

Notice the SST on the case back. It is the Boeing version, not the British/French Concorde.

The above before and after is of a rare Glycine chronograph. 100 were made in 1965 and only 5 are known to exist. This one is featured in a book about Glycine comming out in March.

Here is a link to an article I did on restoring another Glycine watch from bad to good (five it time to download):

glycine repair article

As Tim has pictured above (hi Tim) you get a general feeling about what is classic and restorable. Of course this takes time as my early restorations were no name Swiss with nice movements. I personally look for complication, be it day-date-month, moonphase, chronograph, chronometer and etc. One must educate oneself as this is expensive and there are a lot of non-restorable watches being sold!

Here is a 1960 Omega Constellation that I restored a year ago:

some of the dial work done to the watch as part of the restoration:

So educating oneself is important, I have reference material on watch houses which includes case and movement numbers, style of hands and etc...

It is like knowing which HP calculator is worth spending time on. Do you cannabalize an HP10B for parts for the HP 42S in your collection or vice-versa.

Cheers, Geoff

Edited: 1 Feb 2010, 2:27 a.m.


Hello Geoff,

Thank you for the explanation. Live and learn, and educate yourself in the process.



Great find, Geoff! Please post when this is restored. I am curious to find out if it is accurate against today's techonlogy.


The problem with setting the mechanism is getting the response of the nib to vertically match the correct chart readings.

From what I understand this is done by adjusting the lever system. There is a gross adjustment knob which I have already set to a meterology station at the airport. That is I set the nib to correspond to the reading of 29.98 inches on the y axis of the chart recieved from the met report.

I will chart the error when I am around the machine by comparing it to hourly met reports from the airport. At least I can determine the vertical error at that point. As it is now it would seem to almost be spot on.

Cheers, Geoff

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