(Photograph courtesy of Dana Johnson.)

Wurlitzer brass pipe Caliola, located in a museum in San Antonio, Texas. The case styling is essentially that of a wooden flute pipe Caliola, but without the painted screens over the front and side openings.

(Photograph courtesy of Dana Johnson.)

This oblique view of the brass pipe Caliola shows off the symmetrically arranged rows of capped brass pipes to good advantage.

(Photograph courtesy of Dana Johnson.)

This close-up of several capped brass pipes show the beautiful detail of the turned wooden caps.

(Photograph courtesy of Dana Johnson.)

Rear view of the brass pipe Caliola. Here the up and down sliding back panel has been lowered, so that the roll mechanism and keyboard are closed.

(Photograph courtesy of Dana Johnson.)

The 10-tune Long Tune Roll Frame in the Wurlitzer brass pipe Caliola. Notice the tracker bar tubing below the roll frame shelf is arranged into groups of four. These groups correspond to the spacing of Wurlitzer pot metal four-in-one valves that make up the pneumatic chest.

(Photograph courtesy of Dana Johnson.)

The above photograph shows a section of the pneumatic stack with its pot metal four-in-one valves. The valve units are screwed to a channel board that connects the actual valves to the tracker bar and the pressure chest (that physically supports the brass pipes and contains the individual valves situated under each pipe). The four-in-one valves were a very late development for Wurlitzer, and consequently the market for automatic musical instruments waned with the four-in-one valve seeing only limited use.