This is such a narrowly specific question that I don't have much hope of it being answered, but I came across a statement in a book I'm reading that the Russian Army utilized steam traction engines (basically a road locomotive) in 1870. This seems remarkably early (especially for Tsarist Russia, which I don't usually associate with novel technology), so I was wondering if anyone had anymore information about them - where were the vehicles manufactured? Who designed them? How were they used? Were they successful? If anyone has an image of the traction engine, that would also be extremely helpful!
This is not the sort of challenge I can easily resist.
The Russo-Turkish War dates to 1877-78, not to 1870, but, yes, the Russians did make use of traction engines in this conflict, to move heavy equipment over pontoon bridges they had constructed to cross the Danube.
A British newspaper published in the north-east of the country, the Shields Daily News, published dispatches from Vienna on 26 June 1877, noting:
Vienna, Sunday, midnight. The following highly important intelligence, which may be taken as absolutely authentic, has just been received:-
The Russians have 40,000 men between Galats and Ibraila, and will make Matchin their tete de pont in the Dobrudscha, fortifying it strongly. Their heavy position siege guns will be carried over the pontoon bridge by the aid of traction engines.
And again, the Coventry Times reported on 11 July 1877 that the Russians were attempting to move supplies over the river:
The current of the Danube has been found too strong for a pontoon bridge straight across, and the Russians have consequently been obliged to close the bridge for a day for alterations. It is now serpentine, and another one is being constructed close to it. Two traction engines are now at work levelling the approaches.