Well, how shall we call this watch? You will know that most of the time I go by the shape of the case. This shape is one of the oldest Bulova sold and had model number 156. Then we have one ad in 1924 where it is called Minerva and then it stops. For the ads at least because the model continues to be sold until at least 1929, which is the last year I found this shape. It was sold in a variety of dials: with stripes, with flowers etched and just plain, and various movements with or without second indicator. Versus the older 1924 model, the later models had slightly different engraving as well. They got this V shape at the top and the bottom, as you can see in the subject watch and also in the ad of the Juliana. The Juliana however was a sports model without wire lugs to put a leather strap and with a radium dial. So, in conclusion, the last name we have of this shape is Minerva with afore mentioned differences in the engraving for the subject watch. So "unknown" is maybe better.