update: if you use this image somewhere please let me know, my stepfather loves hearing about his "collection" being passed around the internet :)
Remington "noisless" typewriter brochure.
Copy reads: "Stop and listen for a minute. How noisy is your office and who's making all the noise? Chances are the greatest noise source of all is your secretary. Her clattering typewriter not only makes a lot of noise, but forces the whole level of office conversation to rise above it contributing more to the general office din. How does this noise affect you and everyone else in your offices..."