Thanks again to the many MMD readers who have kindly sent or posted
photos of Auto-Typist pumps.  Detailed photos show that although
Auto-Typist and National roll-changing coin piano pumps have somewhat
different main castings for the hollow frame, the brackets that connect
the rubberized canvas straps to the bellows are the same.  This leads
us to the conclusion that one company supplied the other, or that
Monarch could have supplied pumps to both.

Since Auto-Typist, AMI (previously National) and Monarch all remained
in business long after the end of the coin piano era, it seems
plausible that one of the first two companies could have supplied the
other, or that Monarch could have supplied pumps to both of them.

Art Reblitz
Colorado Springs, Colorado
http://www.mechanicalmusicpress.com/ 
http://www.reblitzrestorations.com/