Rudolf Johnson was another R. Johnson, but based on the time period and eyebrows, my guess is Dick Briefer who used the pen name as per www.bailsprojects.com
The three pages are scattered through the book.
Art looks similar to It's Patented feature.
Art looks imatative of the other It's Patented sequences but not the same. My uneducated guess is that this unsigned sequence (the others were all signed) is by a different artist. This sequence is the only one to include "United States Patents Have Been Granted On The Following Devices..." in bold print.