I have inherited an old New Home treadle, and have established it's manufacture year as 1890. Unfortunately, I have no instructions to go with it, and I can't figure out how to thread it. Although I learned to sew on a treadle in the 1940's, that was many moons ago and a different manufacturer, and I don't think I would remember how to thread it if I had it. This one was my aunt's and I would love to try it out. Any suggestions?