G'day Mark/Rod Garfield,

I have seen 19th century illustraions of 9-stringers, so they certainly were made in factories. The ones that come to mind were woodcuts or (more likely) steel engravings of the type that I have seen illustrating music (and other) items in old Scientific Americans. I have some in a Dover illustrators' source book on Music.

I also remember reading that Mudcat's Art Thieme made a modified 9-stringer of one of his guitars (a Martin, if I remember correctly) when what turned out to be incipient MS, started to affect his playing. It caused a bit of angst at Martin ... but it helped him in just the way that others describe above.