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From: jbm@aurora.UUCP
Newsgroups: misc.wanted,rec.misc,sci.misc,soc.culture.misc
Subject: Re: Technical terms and rules of thumb
Message-ID: <640@aurora.UUCP>
Date: Fri, 20-Mar-87 19:12:17 EST
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Posted: Fri Mar 20 19:12:17 1987
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> I wonder where the term RULE OF THUM came from?

I doubt this is the true answer to your question, but one
"rule of thumb" for esimating the visual size (in subtended degrees of
visual angle) of an object is that the thumbnail subtends about
one degree when held at arm's length.

-- 

	Jeff Mulligan (jbm@ames-aurora.arpa)
	NASA/Ames Research Ctr., Mail Stop 239-3, Moffet Field CA, 94035
	(415) 694-5150