Aren't primes and foot marks two distinct typographic marks? I've always been under the impression that foot marks (and inch marks, for that matter) have vertical axes, while mathematical primes (and double-primes) ought to be slanted. Please clarify this, someone! :-)
They're the same thing.
Unicode defines the following code points:
(In case the above symbols aren't rendered properly on your browser, they're all angled.)
There are other variants of the prime scattered throughout (reversed, modifier letter, and so on), but there is no separate code point for a foot symbol. The closest there is is FOOT, SQUARE; it's defined in the Miscellaneous Technical Range and it looks like a prime hanging inside an opening at the top of a square box.
The Unicode Character Names Index does have entries for feet and inches, but they are simple cross-references to the entries for PRIME and PRIME, DOUBLE, respectively.
The Wikipedia article on the prime symbol supports this.
Perhaps the confusion stems from the fact that on typewriters, feet and inches were represented using the same upright symbols used to represent apostrophes and quotation marks.
I think you're right about the confusion...as least mine, anyway! The "dumb" apostrophe and quotation mark are to blame - they are not acceptable substitutes for prime and double-prime.
Thanks for the clarification.
--Michael.
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// love what you do or do something else. //
Michael Ebert -- graphic designer, jazz saxophonist, horror movie devotee
http://homepage.mac.com/mwebert
mwebert@mac.com
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Yes, although if you use an italic version of them, the dumb apostrope and quote work pretty well as primes/feet/inches.
T
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