It appears to be some manner of Traction Engine. The odd cylinder amidships is similar to that of a vertical boiler used on early steam engines:
Yet, the horizontal-cylinder frontend of the vehicle is similar to a horizontal-boiler Steam Traction Engine (which most steam traction engines had).
So, if this is an imrpovised Armoured Steam Traction Engine, why does it appear to sport both a vertical and horizontal boiler? Furthermore - how come it looks like it only has the two main wheels in contact with the ground? I presume there are other wheels, they are just not visible in the picture.
Very odd, thank you for sharing!
---Vil. P.S. I wouldnt want to be in a steam powered AFV when it got penetrated by enemy fire!
It really looks more like some kind of portable fumigation trailer to me- If I read Polish I'd know for sure! Does the caption say something about "improvised? The author of Asian Odyssey ended up running one for the Soviets in the 1920's, so they were in use then. Here's a link to a modern machine with a few structural similarities: http://www.timmenterprises.com/machines/steamer.htm Andrew
I typed 'woz bojowy', which can be seen in the photo's caption, into Google image search to see what I cold find, and it pulled up loads of images of fire engines...
I remember seeing a Warner Brothers or Disney cartoon involving a non-motorised fire engine with just such a water carrier. I believe it was "Donald Duck". In his antics, he would accidentally spill much of the water, out of the large cylindrical container, all the while needing to go fight a fire. But if my memory is not decieving me, I have not seen that cartoon in leagues of years.
My one conclusion is that... This was an Armored Firefighting Traction Engine.
'Woz bojowy' translates to 'war car' or 'chariot'. The thing was based on a motor plough called 'Praga' produced by Erste Böhmisch-Mährische Maschinenfabrik (BMM - later known as CKD) from 1914.
I think that the red lined area A is probably a commander's turret and not a boiler. I've lightened the image a litttle and I think that red line B is a machine gun in some form of sponson. There must be a third wheel at the front to balance the monstor and for steering.
Looking at a history of the Praga motor company the motor plough was developed between 1914 and 18 when the company suspended manufacture of luxury cars and was switched to military production producing trucks etc. The implication is that this was originally some sort of military vehicle. I can find no photo but I have discovered that the KuK forces used similar two wheeled motorised vehicles as the front half of a composite vehicle, the rear half being the gun its self. So this could have started out as a sort of motorised limber. None of these were armoured of course.