I checked the boards and Cecil’s archives, as well as Google, but nothing that I referenced explained how large numbers are expressed in Roman numeral notation. It seems that the thousands (expressed by the letter M,) is as high as you can go in Roman numerals. While people in ancient times probably never dealt with currency units, census counts or any other application that called for the use of numbers in the millions and beyond, I would think that at least they had a system to express these numbers in theory.
Everything you ever wanted to know about roman numerals:
http://www.wilkiecollins.demon.co.uk/roman/intro.htm
Excerpt:
I have usually heard the vertical bar thing used for large numbers. So with that, the M with a vertical bar over it is the largest single symbol, representing one million.
Nah, you can put as many vertical bars over the numeral as you like.
Two vertical bars = 100,000 times
Three vertical bars = 100,000,000 times
and so on.
oops, that’s 1,000,000 and 1,000,000,000 respectively. OWAGIA (Oh, what a goof I am!)
It would be interesting if anyone knew the largest roman numeral recorded before the advent of the decimal system. I wonder if they ever used more than one bar.
I can’t imagine why anyone in the Roman Empire would have used more than one bar, unless they were like me as a kid. I have an old elementary school notebook with a half of a page full of 9’s, just so I could see what was the biggest number I could write. The Roman kids had an advantage though—one line is as good as three digits!
It would be a pretty more numbering system that limited how high you could go. The stacking horizontal lines over numbers allow you to extend towards infinity. End of OP.
Just to correct two assertations made in the OP: the Romans certainly dealt with “currency units” (by which I presume you mean large value exchanges of currency) and censuses. In fact, the word census is Latin:
and,
I guess I should have been more clear about this. I know that currency (or monetary) units as well as census-taking have been around since the beginning of civilization. What I meant here is that ancient cultures likely had no need to use very large numbers (i.e. millions and beyond) for these two particular applications that I provided as examples.
My Webster’s New Twentieth Century Dictionary Unabridged gives numerical values for many of the letters besides the well-known I, V, X, L, C, D, and M. The letter with the greatest value (without an overbar) is Z = 2000. Some of these alternative letters are called “medieval Roman numerals” (e.g. Z) while some are just Roman numerals (e.g. B = 300). You can also find these numerical attributions online in the Dictionary of One Letter Words. My question: where in ancient or medieval times were these additional letters used and for what purpose? Some of them, like O = 11, seem rather pointless.