inch thick. The pipe sections averaged 19 feet in length, containing each 8 sheets of iron 6 by 3 feet. The laps were 1-1/2 inches
at the joints and single-riveted, the rivets being driven 1-1/4 inches
from centre to centre in 1/16-inch-diameter holes. To each sheet of
iron 77 rivets were used, 28 on the longitudinal and 49 on the circular seams. The heads of the rivets were 1/2 inch in diameter by 1/16 inch thick, and the shanks 1/4 inch in diameter by 0.44 inch long. The rivets weighed about 1/8 ounce each, or 128 to the pound.