I wish I had pictures of the lathe I first learned to turn on. It was my Grandfather's and came out of an old mill that used the old, long flat belts from a PTO. When my Dad had it, it consisted of two heavy and somewhat ornate cast iron ends/legs with pockets into which heavy timbers fit to form the bed. I guess they were about 4'x8" and of whatever length you wanted, with a space between them which held the mating timber/tailstock arangement.
My Grandfather had cut a grove in the end for a v-belt where it would have originally just been flat, and hooked up a small motor. I remember large cast wheels and wooden t-shaped pieces that would slide along the bed.
I was 10 or 12 when I first used it and at that time it was about 6 feet long. Many years later while working with my Dad doing construction/renovations, we had a customer who had two 10 foot long turned columns that were rotten and needed to be replaced. We removed the existing timber bed and replaced them with 12 footers. Glued up 2x10x12' pieces until we had 2 pieces that were 10 x 10 x 12' and mounted them on the lathe. The initial power on was quickly a power off! The motor turned WAY TOO FAST! My Dad decided to try conecting an old 1/2" drill to the shaft of the motor. It was a variable speed drill with a top speed of 300 rpm. I turned those two columns while my Dad operated the trigger on the drill. I think we split $300 for that job! While they are most likely not in very good shape now, they are still there, almost 30 years later. But, like I said, I don't have a picture!