The enclosed photo shows what appears to be a version of the Burell-Boydell complete with footed wheels. However it looks a mite more modern than the 1857 model, but the essential format is the same- driver in front of the boiler fireman behind. Unfortunately its source provides no information other than to claim
a) It's American b) It's the world's first track laying vehicle
The original machine was British but maybe Burell marketed it in the US? Or some enterprising Yankee engineer 'nicked' the idea? The original probably was the first track layer.
I first saw that photo in an old Kenneth Macksey book about tanks; the photo I posted is from the Science Museum.
Interesting that your source says it's American - I've never seen that said anywhere, but I have always suspected that it is not a Burrell machine (though those are definitely Boydell wheels) so who can say? I agree that it is almost certainly a later machine than the 'classic' Burrell-Boydell, in which case it clearly isn't the 'world's first track laying vehicle'.