Subject: The meaning of a symbol
Name: Charles Fontaine
Who is asking: Other
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,
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."
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