Some time ago I found this image of an advertisement for Ely-Norris safes inside York safes. It is supposedly from 1918 and shows the working relationship that Ely-Norris had with York at the time. What I also find interesting is that the ad mis-spells the name of the company, at the bottom, as "Eli-Norris".

Click image for larger version.  Name: 1918 Ely-Norris and York.jpg  Views: 43  Size: 90.7 KB  ID: 8819

The image is from http://www.officemuseum.com/filing_equipment_safes.htm and in particular http://www.officemuseum.com/1918_Yor...Co_York_PA.jpg.