The Mekarski system – compressed-air propulsion system for trams

Louis Mekarski was a Polish engineer and inventor living in France. He is famous for inventing the so-called Mekarski system of compressed-air powered trams in the 1870s.

His system was used in some of the cities in France and the US as an alternative to horse-powered and steam-powered trams.

Preserved Nantes compressed air tramcar at the AMTUIR museum. Photo credit

There was a problem with the system whereby the expanding air from the compressed-air propulsion was cooling and causing the formation of ice in the power cylinders.

So, Mekarski’s solution to this problem was to create a boiler – a bouillotte – that would produce steam to heat the expanding air and prevent it from turning into ice.

Tram, Mékarski system, experienced by Northern Tramways (of Paris) in 1875

 

Mekarski tram in Paris during 1910 flooding, the top of the hot water tank and the regulator can be seen in front of the car; the 9 air tanks are below the tram.

The engine was single-staged and the expanding air was transmitted in one piston and then exhausted. So, the re-heating of the expanded air was in the interval between it leaving the tank and before entering the engine.

The hot water tank bubbled air through a hot water tank, sucking the hot vapor to improve the engine’s range.

An improved engine contained a high-pressure cylinder of 140 centimeters operating at 23 – 68 kg/sq in a low-pressure cylinder of 20,32 centimeters, with the same length of the piston stroke.

Mékarski tram – to the old station of Saint-Quentin

 

Another view of a tram Mékarski OGS 1900 types.

Mekarski’s system was most useful in congested streets and in tunnels since the compressed air didn’t produce smoke or flames,  and it didn’t disturb horses or fill the carriage with soot and sparks like a steam engine.
The system was tested in Paris in 1876 and introduced to the tramways of Nantes in 1879. The system was later used in England and the States.

Mékarski tram in Nantes.

 

Propelled Mékarski in Bern, Switzerland

As for Mekarski, well, he had other inventions and patents. One of them is a similar system of compressed air that he created for automobiles together with an early aviator – Paul Lucas-Girardville.

Waste heat from an internal combustion engine generated steam, which was mixed with compressed air from an air compressor driven by the ic engine. The air/steam mixture then drove a separate piston engine which propelled the vehicle. This system pre-dated the better-known Still engine.

Propelled Mékarski system streetcars in Bern

Mékarski also obtained a patent for spring wheels for vehicles.