That's very interesting about the catalog differences. I'd like to check that out sometime. The 1915 on the Pearson Prisco catalog appears to have been added to the scan. Notice the different font, the unbalanced placement, and the sharper resolution. The Prisco catalog is somewhat odd in that it has both the No.165 and the No.175 hot blasts which are the same lantern except for the beaded-chisel tee on the 165, which I call the Buckle Tee. I'd love to see the 1912 Rayo/SOCONY catalog sometime. Unfortunately Prisco/Rayo is a bit down my list of research projects right now.
Bob