Subject: The meaning of a symbol

Name: Charles Fontaine
Who is asking: Other
Level: All

Question: Is there any significance to the bar placed over some Roman numerals?

It has always been my understanding that a bar over a Roman numeral indicated that it is multiplied by 1000. Thus

This was confirmed by two sites I found,
http://www.deadline.demon.co.uk/roman/intro.htm
and
http://www.cod.edu/people/faculty/lawrence/romaindx.htm
however the first of these references also contains the statement "in some cases the horizontal bar was used to show simply that the letters were being used as numbers."