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Re: "em" should be horizontal, "ex" vertical

From: Clive Bruton <clive@typonaut.demon.co.uk>
Date: Mon, 11 Aug 97 13:12:18 +0100
To: <www-style@w3.org>, <www-html@w3.org>
Message-ID: <1340817281-79081819@battersea.indx.co.uk>
Walter Ian Kaye wrote at 11/8/97 12:23 pm

> > Correct, the definition of an "em" is a *square* of any given body size,
> > ie 9pt*9pt, 24pt*24pt, 72pt*72pt are all ems.
>And here I thought an em was a square the width of an uppercase "M".
>Silly me.

An easy mistake, since that is the theory, except it doesn't make much 
sense when one considers extended and condensed type forms.

> > The correct term for a 12pt
> > em is a *pica* em as pointed out, an em is a relative unit.
>I've never heard of a "pica em" -- only just "pica" (1/6 of an inch), and
>picas are indeed used for both horizontal and vertical.

Pica is just a name for 12pt type (other sizes have "names" too), not 
sure whether one could say pica (your use) is an abbrieviation of pica 
em, certainly they are dependent on each other. Using the metrified point 
system, 72pt to the inch, 12pt is 1/6 of an inch.

-- Clive
Received on Monday, 11 August 1997 08:15:07 UTC

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