Carpenter's marking line (chalk line, mòdòu, sumitsubo)
Cordel entintado de carpintero (chalk line, mòdòu, sumitsubo)
- Date
- c. 2500 BCE · confidence low
- Place
- Giza, Egypt
- Credited to
- Egyptian builders; Chinese tradition attributed to Lu Ban
- Field
- Tools
⚠️ Disputed: the sources disagree.
What it is
A cord soaked in ochre, ink or chalk which, stretched and snapped against a piece, marks a long straight line in one operation. Egyptian builders used it to guide the cutting of blocks, and in China and Japan it developed into the mòdòu and sumitsubo, with an ink reservoir and reel.
Red ochre marks on Old Kingdom Egyptian blocks point to its use, but the object itself is not clearly preserved. Chinese tradition credits the mòdòu to the carpenter Lu Ban (5th century BC), a semi-legendary figure; the origin may be independent.
What it led to
- setting out straight lines on masonry, beams and planks
- the mòdòu and sumitsubo, emblematic tools of Chinese and Japanese workshops
- the builders' chalk line still in use today