Lempor ejector

The Lempor ejector is a steam locomotive exhaust system developed by noted Argentine locomotive engineer Livio Dante Porta. The name is a combination of those of Maurice Lemaître, Belgian locomotive engineer, and Porta.
Operation.
In a steam locomotive, draft is produced in the firebox by exhausting the steam coming from the cylinders out of the chimney, or also by a blower. The Lempor ejector ejects differently from the conventional blastpipe; as one cylinder ejects it creates a vacuum in the other cylinder, thereby requiring less power to drive the piston.
Results.
The Lempor exhaust is claimed to deliver a 100% improvement in draughting capacity over traditional exhaust systems and a 40% increase in ejector performance.