The Baldwin Gas Mechanical BGM         Sarah's Remarks

We all love a mystery and this family of locomotives offers a few. First of all, there is her name. The official US title is ‘Baldwin Gas Mechanical’ but her crew preferred the term ‘tractor’ although the term already applied to that ubiquitous bit of farm machinery. The attitude spread to France where the official name was ‘locomotive à essence’ (petrol) where the name locotracteur stuck. http://appeva.perso.neuf.fr/imgapp/t33-01.jpg

Photo. A model in 16mm scale made from a Wrightscale kit by the late Henry Holdesworth.

There is also power in her mystery. Scrutiny of original Baldwin documents – the 1919 catalogue – explains that she was supplied in 35hp and 50hp versions. Richard Dunn suggests that the original order may have been for 20 and 40 hp locomotives, but given the famous just-do-it philosophy of the Baldwin Works, this may have changed to suit the engines available. It all seems very simple 35 and 50 hp were delivered – 35Cv and 50Cv (chevaux/horses) to France.

And yet … the myth of the 20, 40 and 45 hp locotractors persists quite obstinately. In a splendid, well researched book of 2002, we see a photo of a US train passing over a wooden bridge of the Wild West type. Below are the august Paris-Strasbourg mainline and the equally regal Canal de l’Est. In the background is the elegant arch of a stone bridge. The cheery tourists are hitching a ride on a Péchot wagon while being hauled by a cheeky Baldwin locotractor, also carrying some passengers. The caption reads ‘The locomotive is Baldwin 45hp no 7023’ How do myths develop? In this case, one suspects that it is through careless labelling by the war photographer.

At the beginning of the War, steam locomotives were used on trench narrow gauge, but both the French and the Germans soon realised that internal combustion locomotives had many advantages, chief of which being they were less visible. They were also less likely to emit stray sparks – given the combustible environment, quite an advantage. The British and French had their own designs, but they were just not being produced in enough numbers. When the USA entered the war, they looked to Baldwin who was already delivering locomotives in large numbers to both the French and British. We must remember that the powerful reliable internal combustion engine that we so take for granted was only just emerging.

            

Baldwin combined existing technologies. It was accustomed to cast steel bar frames, as used for example on the Baldwin 4-6-0T it was producing for the British War Department. It developed existing gear boxes. Usually, at the time these may have been 4-speed, but the BGM had only two. Its usual top speed was 6mph though 12mph was a theoretical maximum. It had an electric starter for the motor and lights, a boon for the atrocious conditions. The motor modified existing technology. Each cylinder was a separate piece for ease of maintenance

Trench conditions did not allow for turning and so machines such as the Péchot-Bourdon could be run in either direction. The Simplex 40 hp and the BGM solved the problem by having the driver sit side-on.

Telling them apart? The divided windscreen on the 50hp version consists of a pair of rectangles whereas those on the 35hp are a pair of squares. The transmission jack shaft crank is larger on the 50hp version. The pair of louvres in the bonnet next to the cab are narrower than the third louver in the 35hp version. All three are the same width on the 50ph.

Was the BGM loved? It was certainly more convenient than a steam locomotive, but it did have problems. Large, tallish and balanced on four wheels, it tended to derail and topple too easily. Most squaddies would have liked a four-speed gear-box, it would have prevent strain on couplings. The War Department Simplex and the French Schneider were more popular at the time, so is reported. Yet, in a cold dawn, with supplies running low, throb of its arrival and the sight of its angular bulk looming out of the mist must have cheered many a heart.

As so many were produced – 600 50hp for France, 126 50hp for the AEF in France and at home, 65 35hp - many survived the Great War and some were sold off for War Surplus, finding their way on to agricultural and industrial lines. They were often customised, a process that fills Malcolm with horror. A survivor at Froissy was re-gauged. Another went to the Festiniog Railway- Moelwyn.http://www.rmweb.co.uk/community/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=381723  ‘Malheureusement’ scolds Jacques Pradayrol of APPEVA who is of the same mind as Malcolm, they gave it a front bogie to help adhesion. To me personally, change is part of the process, a labour of love, even. Today, judging by the interest in this highly distinctive locomotive, the BGM has puttered its way into many hearts.