Scotty Greene asks in the 20.02..02 MMD for help in determining the age of
the Wurlitzer 153 band organ in the DeBence collection.  He says that it
has a "player piano style air chest," not the unit block action that is
usually found in Wurlitzer band organs.

Judging from that, I would say that the DeBence band organ is a very early
model of the Wurlitzer 153.   Wurlitzer's unit block action, consisting of
individual valve blocks rather than using one solid valve chest as is
typically found in player piano actions, did not exist until Chicagoan
Charles Jameson invented the unit block.  Jameson filed his invention with
the U.S. Patent Office on May 24, 1918, and was granted patent no.
1,367,263 on February 1, 1921.  In Wurlitzer band organ ledgers, the unit
valve stack is called the "Jameson Chest."

This makes it likely that the DeBence 153 predates 1918, when Wurllitzer
switched to the Jameson chest design as a vast improvement over its old
chest style that did not allow the easy removal and repair of defective
chest valves.

Wurlitzer's 4-in-1 metal valve block, introduced later to replace the
Jameson unit block, was a big step backwards, in my opinion, but it must
have been easier and less expensive for Wurlitzer to produce than the
wooden Jameson valves.

Matthew Caulfield
Irondequoit, NY