Anatole Mallet

Jules Theodore Anatole Mallet[1] (23 May 1837 – 10 October 1919) was a Swiss mechanical engineer, who was the inventor of the first successful compound system for a railway steam locomotive, patented in 1874.

[3] He subsequently designed an articulated compound system with a rigid chassis at the rear carrying two high-pressure cylinders, and two low-pressure ones mounted on a swivelling front truck.

[4] This was first used for a series of 600 mm (1 ft 11+5⁄8 in) narrow gauge locomotives specially built by the Decauville Company in 1888 for the Paris Exposition of 1889.

Large numbers of these, mostly a 2-8-0 derivative, were built for Russian and Hungarian railways making them the most-produced type of tandem compound locomotive.

Z. Kordina's design for Hungarian State Railways was a similar 4-4-0, although outside-framed and with the low-pressure cylinders ahead of the high pressure.