The bellows

The electric blower is mounted in a sound proofed box which is connected to the organ by a flexible tube. This technical solution requires a reservoir which runs practically the full length of the organ. This type of reservoir has a rocker system to regulate the air flow. This allows a constant air supply with no fluctuations in pressure. This is particularly necessary if tuning to meantone with pure thirds, where the slightest variation in pressure would completely negate the tuning.