The photo below is of an Ingersoll wrist watch I picked up on eBay. The watch was made in Great Britain, has 7 jewels and has a lever escapement. The movement is a calibre 602 (Thin Line). It is a fairly well made watch considering it was made for low cost mass production. It was manufactured in the early 1960s.
Here's another Ingersoll movement. It's a Swiss made calibre 1229 which uses a pin-pallet escapement which is less expensive (and less accurate) than a lever escapement.
The Ingersoll company was started in 1880 in New York by the brothers Robert and Charles Ingersoll. They set up a mail order company specialising in selling items at $1. In the mid 1890s they started selling pocket watches for a dollar, creating the advertising line: 'Ingersoll - the watch that made the dollar famous'.
After the wall street crash in 1929 Ingersoll Ltd was launched as a British company, then after the Second World War it joined with Smiths Industries Ltd and Vickers Armstrong creating the Anglo-Celtic Company Ltd. Ingersoll Ltd pulled out of the venture in 1969.