A Westbury "Hermes" twin cylinder overhead cam engine. It's complete and turns over freely with good compression. Two of the mounting feet are cracked through and require repair.
One of the rarer Westbury designs, I've never had one in before and was surprised, when this one arrived, just what a size it is.
Length 17 inches
Width 8 1/4 inches
Height 12 inches
Flywheel 4 inch diameter