This file is in the public domain because this image is patented under U.S. law with the inscription "Reg. U. S. Pat Off. Made Only By Tichnor Bros" circa 1948. According to 35 U.S.C. § 154, the term of patent has expired 20 years after the application was filed. As for copyright, the U.S. Copyright Office, Circular 15a states that works published with notice of copyright or registered in unpublished form on or after January 1, 1923, and prior to January 1, 1964, had to be renewed during the 28th year of their first term of copyright to maintain copyright for a full 95-year term.