The assistant carefully sets a metal ruler next to the object in the hole.
So they'd beat all 100 of us with metal rulers.
Turning a metal ruler so that it ran from the red dot, Burbank drew a line of his own.
Use a metal ruler or carpenter's level as a straightedge, the longer the better.
If you have confidence in your visual judgment you can do this by eye, otherwise use a long metal ruler.
After two failures, Bonassoli eventually agreed that it could easily detect a metal ruler.
Then a metal ruler was pressed against one ear.
"And what do you call that little metal ruler?"
Hold a long metal ruler against the tracks to check for straightness and make sure all sections are in line.
The metal ruler flashed and the skin split across my knuckles.