intersting engine for 1918

interesting engine and story , Archibald Richardson was the brother of Mervyn Victor Richardson of Victa lawnmower fame and the Victa Airtourer aircraft , the brothers built a small monoplane in 1918 with this engine and contra rotating props called the Wasp which is all mentioned in the story on the link below
http://www.powerhousemuseum.com/collection/database/?irn=135787

“Engine Description “
Twin row rotary aero-engine. The 6 cylinder engine is air cooled and operates on a two-stroke principal. The rear row of cylinders ‘supercharge’ the front row and the crankcase and crankshaft rotate in opposite directions. Two wooden propellers are attached to the crankcase and crankshaft, resulting in the contra-rotation of the propellers.

I see on wikipedia a contra-rotating propeller was patented by F. W. Lanchester in 1909 which was a surprise to me

Mervyn Richardson Bio
http://adb.anu.edu.au/biography/richardson-mervyn-victor-11517