Jewelry from the 1930s marked "Otis" looks a lot like the pieces produced by Wachenheimer Brothers. The reason is that in 1934, Edward O. Otis, Jr., purchased their assets and continued to operate the plant with the same personnel. You can read more about Otis jewelry in these two articles: “Bracelets by Otis: A Surprising Connection” and “Jewelry Sleuthing: A Philadelphia Story”.
