What is that little letter "o" with a line below it that is set so the top
of the "o" is at the top of the em square and the line below it is about
midways down. It is sometimes used in the abbreviation for "number." As in
"N" + the character in question.
Not to lay to much on the group at once but people used to abbreviate things
like this a lot. The name "William" for example would be abbreviated as "W"
plus a little "m" with a line below it as described for the "o".
Any ideas on this?