Anatole Mallet

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.[2] He is known for having invented three important forms of compound locomotive.

In 1876 he introduced a series of small two-cylinder compound 0-4-2T tank locomotives for the Bayonne-Anglet-Biarritz Railway in France.[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. This was patented in 1884[2] with full rights granted in 1885.[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.[4] This arrangement became known as the Mallet locomotive. The final developments of these in the USA were some of the largest steam locomotives ever built.

A third compound locomotive, less well-known, was a tandem compound developed in 1890 for SACM as a collaboration with Alfred de Glehn and the Russian A. Borodine.[5] The high and low pressure cylinders were mounted on a common axis, with the high pressure ahead. Unlike the US tandem compounds, the high and low pressure cylinders were cross-connected between sides, which also required them to be receiver compounds with an intermediate reservoir as a pair of curved pipes passing through the smokebox. 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.[5]

He was awarded the Elliott Cresson Medal of The Franklin Institute in 1908.

  • Early Mallet 2-cylinder compound locomotive working the Bayonne-Anglet-Biarritz (B.A.B.) Railway
    Early Mallet 2-cylinder compound locomotive working the Bayonne-Anglet-Biarritz (B.A.B.) Railway
  • SCB Ed 2x2/2 [de], a typical normal-gauge compound Mallet tank. Note the larger diameter of the low-pressure front cylinders.
    SCB Ed 2x2/2 [de], a typical normal-gauge compound Mallet tank. Note the larger diameter of the low-pressure front cylinders.
  • One of the last US large compound Mallets
    One of the last US large compound Mallets
  • Mallet tandem compound, Russian locomotives class П [ru]
    Mallet tandem compound, Russian locomotives class П [ru]
  1. ^ "Google Patents". patents.google.com. Retrieved 2022-09-12.
  2. ^ a b Ransome-Wallis, P. (1959). Illustrated Encyclopedia of World Railway Locomotives (2001 republication ed.). Dover Publications, Inc. pp. 500–501. ISBN 0-486-41247-4.
  3. ^ Van Riemsdijk 1994, pp. 10–11.
  4. ^ a b Durrant, A. E. (1974). The Mallet Locomotive. Newton Abbot: David & Charles. ISBN 0-7153-5904-5.
  5. ^ a b Van Riemsdijk 1994, pp. 37–38.