This was a very early use of piston valves.

The huge annular piston valves can deliver up to 75 m3 of water per second.

The mellophone has three piston valve, operated with the right hand.

Unusually, outside admission was used for the piston valves of the cylinders.

The piston valves were of the outside admission type.

With piston valves, the steam passages can be made shorter.

As a result, the following 126 engines were supplied with piston valves on both sides (429.100-225).

The origins of this type of piston valve are not precisely known.

It was a cross compound with piston valves across the high pressure heads.

The most common custom design used is the piston valve.