I am an English and journalism teacher. Recently I was reading a story to a class that said... "he was font of knowledge." I have always thought of the phrase as "a fountain of knowledge." As a journalist, a font is a type style like Times or Helvetica.
I was curious if the use of font in that case was wrong or where that branch of the word came from.
The words are probably related to Latin words for flow, pour, and melt. Many dictionaries list font as an alternate form of fount, meaning fountain or source of water.
As for what the typeface meaning comes from, see this entry in the Online Etymology Dictionary: font
So one could have a font iron baptismal font? (That is, 'font iron' meaning 'cast iron'.)