Early Modern Publisher didn't distinguish "i" and "j", though we're almost certain (almost) that British people back then pronounced sound "j" in the same way as we did. Thus the name Benjamin Jonson went "Beniamin Ionson" in published texts and Jonson signed "B.I." under his epigram on Shakespeare's portrait.
@manderley Oh my it's so beautiful!!! I'm so jealous of you! Also I believe it's Jonson's own handwriting. Looks like his!
@aglarienenglit
got a photo on this issue in the lib today - tho the capitalised J is printed as J, the little dash is not that detectable