Why do some imperial tape measures have a mark at 16, 32 and 48 inches, and so on?
John Jarvis, Bristol, UK
We pay 拢25 for every answer published in 快猫短视频. To answer this question 鈥� or ask a new one 鈥� visit newscientist.com/lastword. Terms and conditions apply.
Advertisement
This article appeared in print under the headline 鈥淢ystery measure鈥�