S/N 15991 was retailed by Edward J. Dent 61 Strand, 33 Cockspur & 34 Royal Exchange. The movement was made by Gibbons as previously stated. I can not say for sure, however E.J Dent may have examined this watch himself. As you can see rhe firm was located at several locations, and was selling a lot of watches. There was a time in the first half of the 19th Century when the firm assembled and or made their own watches.