Anatole Mallet

Jules T. Anatole Mallet (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.
In 1876 he introduced a series of small 2-cylinder compound 0-4-2 tanks for the Bayonne-Anglet-Biarritz Railway in France. He subsequently designed an articulated compound system with a rigid chassis at the rear carrying two high-pressure cylinders plus two low-pressure ones mounted on an articulated front driving truck, patented in 1884 with full rights granted in 1885. 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. This arrangement became known as the Mallet locomotive.
He was awarded the Elliott Cresson Medal of The Franklin Institute in 1908.