time has passed and I can confirm Thnarg is correct
Mann was part of Mann Egerton who built a lot of aircraft in Norwich by other designers in WW1
They designed a couple of aircraft themselves which were conventional. This one was based on the idea that you could adopt a conventional engine up front to a pusher and retain the forward firing position . Problems with the efficiently of the chain drive meant it was seriously underpowered.
Over to Thnarg!