"According to Canadian folklorist Philip Hiscock, 'The real explanation of 'rule of thumb' is that it derives from wood workers... who knew their trade so well they rarely or never fell back on the use of such things as rulers. Instead, they would measure things by, for example, the length of their thumbs'." (p. 204, emphasis mine. Ms. Hoff-Sommers elaborates further.)
The width of an adult male's thumb across the joint is one inch.
16 posted on 12/30/2005 3:55:13 PM PST by Oztrich Boy
(Free Speech is not for everyone, If you don't like it, then don't use it)