"Looking Straight Up through a Wireless Telegraph Signal Tower on a Battleship" is printed in the lower right corner. Two photos are mounted on grey cardboard with the number "143" on the top of the front side. Photos are nearly identical with a series of metal tubing, wires and bars that seem to form a large cone-shaped cylinder. Description on back of slide explaining how and why wireless signal towers were set up on ships and of their future possibilites. Color: BK,WH, GY