OCTOBER'S MYSTERY TOOL
Line stone
For many readers, including winner Mike Chartrand from North Bay, Ont., identifying this Mystery Tool was a snap: a snap of a chalkline, that is.
This block is used to chalk a string, which is then used to mark a straight line on a variety of surfaces. A string is chalked by running it between your thumb and the flat side of the chalk block. Once the string is coated, it is pulled taut between two points and then snapped (pulled up and let go), leaving a straight chalk mark. This method of marking a straight line on a flat surface predates the construction of Egypt’s pyramids.
Chartrand writes of another use for the chalk block that his father used when putting up drywall: “My dad used to rub it on the face of a newly installed electrical box. He’d position a drywall sheet in its intended place and when the drywall was up against the electrical box, my dad would tap the board gently against the box, transferring chalk marks onto the back of the new sheet. The markings would give him the exact location of hole he needed to cut. He’d also use the same method to mark pipe locations.”
Today, chalklines can be purchased in reel containers that hold powdered chalk. As you unwind the string, it comes out already loaded with chalk. Once you’ve snapped your line, you rewind the string into the container so it’s ready for the next use.
Chalk continues to have a variety of uses. Gymnasts and rock climbers use chalk on their hands to ensure a good grip. Many from my generation used chalk to write on blackboards, which is still the case in some schools. However, those of a much younger generation tell me of whiteboards and dry-erase markers. — George Gouldburn, photo by Roger Yip
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1 Comment
It's look a lot likes the tree caliper that my grandfather use to have in his workshop. He used this tool to measure the diameter of a trunk and, if I remeber good, there was a scale on the beam that indicated the amount of linear feet/board per 8'.