There was mention made recently (sorry, don't recall the thread) about fast-back seat stays.
I came across this on eBay ...check out the seat cluster. Early 1900's? Quite a bit prior to the 1950's, at least, or so I'd hazard.
Look close at the pix of the chain stays, and how chainring clearance was achieved ...it appears four tubes (two shorties at the bb end, and two longies at the dropouts end) with a casting (which resembles a fork crown to me; wish I could see this better) or plate (or something) connecting member ...and do note the tire clearance, too. *Quite* interesting.
antique bicycle Item # 2163480737
http://ebay.com/
A five bolt chainring attachment 1" pitch crankset, too.
...worth a look.
--- brandon davis ---
-- sacramento, ca --