I was cruising Craig's List tonight. I found this photo in an ad.
The machine is lovely and the treadle irons look to be in great shape. I don't know if it is a 31-15 but it certainly is an industrial strength. But one could never, ever sew with it. Unless a little carpentry were involved. Or it is possible that the top is just sitting on the treadle irons and all it would take would be a quick switcheroo ????
Oh dear, sometimes the ignorance hurts me, sooooo much.