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Thread: Ancient Tools - The Plumbline Scroll 4

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    Ancient Tools - The Plumbline Scroll 4

    "As cunning as a fox who has just been appointed Professor of Cunning at Oxford University”(Blackadder)

    This is the culmination of my series of posts about ancient tools. If you have not read the previous posts, Scrolls 1, 2, and 3, this one should still be interesting, but it will be more informative if you read them first.


    The Plumbline Level
    The next tool we will examine in this series of posts on Ancient Tools is the Plumbline Level. This tool is literally older than the bricks of Babylon. Indeed, physical examples have been found in Egyptian tombs. I think the principles that make it work are clear from the attached images and do not require a detailed explanation.

    The most ancient and easiest-to-make type is the triangle plumbline level, also known as the A-level. My grandfather was a plasterer, and used one very similar to this throughout most of his working career.



    Triangle level from the tomb of Sennedjem
    Nineteenth Dynasty, c. 1300 BC
    painted wood
    The Egyptian Museum, Cairo

    It has been suggested that the Egyptians used the triangle level as an optical level too. No physical examples actually exist.


    Detail from the base of the Four crowned martyrs at the Or San Michele church in Florence, Italy, showing a triangle level. This marble was made around 1370-1421 by Nanni di Banco and was commissioned by the guild of stonemasons and woodworkers.


    Miniature of the apostle Andreas from the Book of Hours of John the Fearless, between 1406-1416. The illumination shows an triangle plumbline level and low-angle block plane, with smaller versions of both tools in the background. Planes were the personal symbol of John the Fearless of Burgundy and can be found in other illuminations on his clothing. Ms lat novv acc 3055, Bibilotheque Nationale, Paris, France

    If the triangle’s legs are long, it can span some distance. The legs can also span obstructions




    Screw that stuff. Why not just stretch the beam of the Apostle Andreas’s triangle plumbline level as in the image below? Not sure what the boys in powdered wigs in the drawing below called it, but it looks useful to me.





    Clearly, the idea was not new to stone masons in the year 1415.

    A one-legged chair? That’s one way to keep from falling asleep on the job.

    Cunrad (Steinmetz), a stonemason from the Hausbuch of the Mendelschen Zwolfbruderstiftung in Nurenberg, Germany. Died before 1415. His tools of trade include the typical long A-like level used by stonemasons, as well a a square and a template. He sits on a one-legged chair.





    And then there are the examples of plumbline squares. Imagine that...


    A plumb square from Cassells’ book titled Carpentry and Joinery

    Don’t forget combined plumbline squares and plumbline levels. Fiendishly clever.




    Two types of levels, the A (figure a) and the inverted T (figure b), as well as a plumb bob with a wooden holder (figure c). Image from the book Das werkzeug des Zimmermans by Hans-Tewes Schadwinkel and Gunther Heine.

    From what I can tell looking at old drawings and pictures of these tools, a small bob was used, and a cutout was made in the tool to provide clearance for the bob so the line would fit neatly into a groove in the tool’s vertical leg. When the tool was level, the line would be centered in this groove, and any difference in the gaps to the each side of the plumbline would be easy for the naked eye to detect.

    While references to “sharpening” have been few in this series of posts (it took herculean self-restraint to not mention diamond paste) I just have to show you a flea-market treasure. It combines a triangle level, and two square levels into one tool.




    Check out figures 18 and 19 in the engraving of carpentry tools below. The level is beautiful. I need to make one for myself, with some modifications to the head and diagonal bracing of course, if only to put on the wall over my workbench. Perhaps with some gothic touches like Apostle Andreas’ level. Any suggestions?

    It is interesting how this tool, which was once as common as cats, has been utterly replaced by the spirit level.

    Allow me to end this series of posts with some sound advice:

    “Speak the truth but leave immediately after” (Slovenian Proverb)

    Stan Covington
    Last edited by Stanley Covington; 11-26-2017 at 5:47 AM.

  2. #2
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    Stanley, thanks for posting!

    Steve

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    Interesting as always Stanley.

    The flea market item looks like it has some attachments to help layout a stair stringer.

    Calibrating an A-level would be another interesting story.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

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    Very handy and hard to knock out of calibration even if dropped off of a pyramid.
    Jim

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    Quote Originally Posted by Jim Koepke View Post
    Calibrating an A-level would be another interesting story.

    jtk

    Edit: Stanley has a better way below


    Level (with shims) a flat surface using a water level, and put the A level on it. Then with a plane, shave one foot or the other until it reads level.

    Flat surface: with a plane, joint the edge of piece of 2x4
    Water level: length of clear plastic tubing almost filled with level fluid
    Level fluid: water with a little soap and food coloring

    Note: Using two hands, with one end of the water level in each hand, held up so the water doesn't run out. When held still, the level of the water at each end of the water level, will be at the same level.

    Edit: fixed some wording, and to add: in the old days they could wash out a length of animal intestines for tubing (although I have no idea what they really used).

    Edit Again: Stanley has an even better way below
    Last edited by John Schtrumpf; 11-26-2017 at 9:44 PM.

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    Quote Originally Posted by Jim Koepke View Post
    Calibrating an A-level would be another interesting story.jtk
    Not that difficult.

    1. Place the triangle level on an intentionally sloped and stable surface.
    2. Mark the location of the level's feet on the sloped surface.
    3. Mark the cross-beam where the plumb line touches it. Call this mark Point A.
    4. Switch end-for-end and place the triangle level's feet on exactly the same locations marked out in step 2 above.
    5. Mark where the plumb line touches the cross-beam. Call this mark Point B.
    6. Use your ancient hand-dandy dividers to precisely bisect the distance between Point A and Point B, and strike a line at this point on the beam. This line indicates plumb.

    I like the details of tool "A," the T-level in the drawing below. Notice that Fig VII shows a (brass?) plate with slotted holes and screws. The level mark can be adjusted by loosening these screws and shifting the plate to the left or right as necessary. I think....

    Stan


    Last edited by Stanley Covington; 11-26-2017 at 10:23 PM.

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    Might be related to the "level" they used on the French 75 .....they set it on top of the barrel, to check for the elevation setting.

  8. #8
    Thanks for another interesting lesson Stan!
    (I just received my first plumb bob from Lee Valley, based on your earlier lessons. )

    Fred

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    Quote Originally Posted by Frederick Skelly View Post
    Thanks for another interesting lesson Stan!
    (I just received my first plumb bob from Lee Valley, based on your earlier lessons. )

    Fred
    You are welcome, Fred. Please keep us all posted on your adventures!

    Stan

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    Thanks for the Scroll series, Stan! Enjoy understanding the history of things. Kind of nice to see there are still a few things that can survive the high tech world.

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