Well stone me!
Or words to that effect. I drop in to this thread from time to time hoping for some obscure First World War aircraft, especially a maritime one, so that my treasured copies of the Harleyford series of books will give me that special edge. So seeing this I rushed to "Marine Aircraft of the 1914-1918 War". Is this some Austro-Hungarian creation, an experimental Lohner for example, or perhaps an offshoot of the FBA series? But no, apparently this was not an aircraft that flew during the First World War.
Pusher twin, inline engines, triple bay biplane, snub-nosed (in plan) fuselage, it should be recogniseable. But alas not by me....