"Cloverleaf clusters" is the official title for these packages of 105 mm. artillery shells. Delivery lines are speedy at the large Midwest loading plant where they are made. Fourteen 2,000-pound bombs have been removed from a truck and placed in a freight car in fourteen minutes--and four 4,000-pound "block busters" have been moved from truck to freight car in fifteen minutes. Ravenna ordnance plant. Sourced from the Library of Congress.