Preface is dated March 1925; entire document copyrighted 1925. I regret that I don't remember who contributed this photocopy.
Post seems to have completely recovered from the disruptions of WWI. The 1925 catalog lists ten Post brand slide rules and 13 rules designed for Post by Herman Ritow.
This identical page appears in the 1925, 1927 and 1930 Post catalogs.
The "Sectional View Showing Construction" is reprinted from the 1910 Post catalog and from the 1906-1919 D&P catalogs. It shows Dennert and Pape's DRGM 192052 friction adjusting mechanism. However, All Post brand slide rules (including "Ritow" rules) from 1925 to 1930 were made by Koch, Huxhold & Hanneman, not D&P.
For more information about Herman Ritow and Post "Ritow" slide rules, click here.