Indeed it is a neat machine. Dorothy's, I think, is the first model. I still haven't gotten the progression right as found some later models from the mid 1980s with the same "dealer."
https://sailrite.wordpress.com/tag/s...ewing-machine/ Sailrite evidently badged the later models and then had their engineers develop the zig zag model after the Thompson. I did find a later patent that was assigned to Sailrite.
Janey - Neat people never make the exciting discoveries I do.