World’s Oldest Micrometer – 1776! Who made this thing??

After months of communicating with Ben Russell, the mechanical engineering curator at the Science Museum, London, I finally visited and we took a very close look at the micrometer reputedly made by James Watt.



  1. Pingback: Industrial Vending Machine – Off Hours

  2. stephen bennis

    I can see what could be where washers sat for the base mount, a faint outline(10:18). Or maybe wishful thinking.

  3. Ed Vojcak

    Most likely made by Watt – we must remember that a micrometer did not exist and Watt was thinking on how to make an instrument to measure distance for a specific reason – there were no rules only some general ideas on how to build instruments -refinement came a lot later. There is a similar problem in mathematical proofs – the original proofs had errors that were corrected – just as it been said (I think by Gauss) we see the Cathedral as-built not the scaffolding used to build it.

    BTW thanks for the references.

  4. Antony Hall

    Just reading Simon Winchester’s book ‘Exactly’ ,’How Precision Engineers Created The Modern World’ , if you are interested in engineering and technology, you should be interested in its history. This is a very readable introduction to the evolution of our quest for Precision and Accuracy. While reading the pages on Whitworth’s micrometers I discovered Fascinating, many thanks for the info, I will be back for more.

  5. Todd Barrett

    Don’t you think the marks one the back are from inserting and removing the pins? Using a hammer on soft brass would make marks like that.

  6. Todd Barrett

    Also the “knurling” on the edge could have been used to index the graduations.


Leave a Comment

Your email address will not be published. Required fields are marked *