Soldier riding motorcycle, Aberdeen Proving Ground

View of a soldier riding a motorcycle in a sand pit at the Aberdeen Proving Ground in Maryland. Trucks in background. Label on back: "Aberdeen Proving Ground, MD. Motorcycle groundhog. Vehicle burrows into sand pit but negotiates obstacle at the Aberdeen Proving Ground, Md. with ease. The sand pit is one of many similar obstacles created at the Army's ordnance vehicle proving ground to test power, traction, endurance, etc., all adding up to increasingly more effective vehicles for the Army's fighting men." Handwritten on back: "War workers--Unusual."