How To Date Your Antique Survey Instruments

This section will cover how to date your American made antique survey instruments. 

Dating Tables

We have put together a few dating tables based on serial numbers for some specific makers to assist you in dating some of your instruments.  These tables are either based on known serial number log books from the makers or they are based off of known instruments with sales or makers dates.  The log book tables are more accurate than the sales methods but even the sales method should get you usually within 5 years of the manufacture date. 

*******Click On Makers Name To Jump To Their Dating Table Page*******

Buff & Berger & C. L. Berger & Sons Research Available

We also have copies of the original "Build Sheets" that were used internally by Buff & Berger and C. L. Berger & Sons.  We can research your specific serial numbers for instruments made from approximately 1870's until around 1955.  The very first log book is missing so the earliest serial numbers are not known and there are a quite a few missing serial numbers around the time that Buff & Berger split into two companies. 

We do not have any records for the "Yellow or Light Grey" Berger builders' instruments.  The newest records we have are from 1955 so if your instrument is a newer one we will not be able to help with the research.

The "Build Sheets" were used internally and they told the shop how to build a specific instrument to the specifications of the customer's order.  These records have dates, customer or dealer/agent names , model numbers, and any options that may have been installed.  They are copies and most of them are hand written so some can be hard to read but we can research them for you for a research fee of $20.00.  If you would like us to research your instrument please contact us and we will let you know if we can find your specific serial number.  Please do not try and pay the fee until we contact you that we do have the record.   If we have the records for your specific serial number we will email you and let you know we have the records and how to pay the fee.  Once the fee is paid we will email you a digital copy of the original build sheet.

Coming Soon!

We will be adding a completely new section that discusses timelines that describes approximately when American makers changed certain designs on their instruments.  This will cover things like telescope designs based on the optics available  during certain times.  Tangent designs, tripod head styles, limb figures and numbering, engraving, dividing of the circles, etc.

This new section will not be an exact science as we describe different designs of American makers and some makers were slower than others to get the new designs so they are harder to date than others but our goal is to get you at least in the right era.

Dating Your Instruments In Depth