A Birmal patent aluminium lawn tennis racquet circa late 1920s, patent number 219535, a rare version with a wooden grip, piano wire stringing, once ow

A Birmal patent aluminium lawn tennis racquet circa late 1920s, patent number 219535, a rare version with a wooden grip, piano wire stringing, once owned by Eric A. Cross, Tennis Director & Consultant, and a Wimbledon competitor, who received it from Birmal after he had suggested the use of aluminium for racquets, so this is probably a prototype and is scratch signed by Eric Cross to the grip in the form ERIC.A.X