LAUNCHING OF SHIPS IN RESTRICTED WATERS. 29 
We civil engineers of the shipyards at that time were suffering from lack of knowl- 
edge of just this sort of thing, which Commander Saunders deserves great credit for 
giving us now, completing, I understand, his first paper. 
We tried to economize all we could at the shipyards in the matter of adequate launch- 
ing room and cut down the dredging again at Bristol, Pa. We wanted to be safe, but did 
not dare to jeopardize these ships. We felt every one of them was a needed contribution 
to the success of the war, and we could not take a chance by trimming too much. 
The launching arrangements were crude. On one occasion a number of distinguished 
men were present at a supposed launching at one of these shipyards, and the ship did not 
move—would not go down. I believe she had been down on the grease a little too long, 
but there was some doubt about the reason. On the other hand, I have seen them “‘burn 
up”’ the ways at the end of the run as they took the water. These two extremes show 
the crudity of the general arrangements; even a change of lubricant might have equalized 
the speed which was wanted. 
This matter of being able to limit the run of the ship isimportant. It was extremely 
important three years ago with our one hundred and eighty shipyards for the merchant 
marine being built or extended on water fronts often restricted in width. 
Mr. Epwin B. SaptLeR, Member (Communicated) :—The writer, while superin- 
tendent of the Harlan & Hollingsworth Yard at Wilmington, Del., in 1901, made use of 
weights dragged by the ship for checking same when launching the S. S. Denver, as 
follows :— 
Weight of ship when launched, 2,650 long tons. 
Two weights were used on each side of ship, one of 25 and one of 30 tons, or 110 tons 
in all, equal to 4 per cent of the ship’s weight. 
The weights were made up of punchings in rectangular boxes of plates bolted to- 
gether and connected to ship by her own chains 2 14-inch diameter of such a length that 
the 25-ton weight nearest the water dragged first, the 30-ton weight not starting until 
the former had moved some distance. As a shackle on the 25-ton port weight broke in 
starting, the 30-ton weight dragged over the stationary 25-ton port weight, the latter 
with the 25-ton starboard weight checking the ship before the starboard 30-ton weight 
started, or after the port weight had dragged 125 feet. Hence the ship was checked by 
a total weight of 55 tons or a little over 2 per cent of her weight. 
Being associated with the Oscar Daniels Company, of Tampa, Florida, who are 
building 9,500 deadweight ships for the United States Shipping Board, I recommended 
drags on launching these ships, as two of their ways are restricted in launching space, 
We used the ship’s chains for weights, coiled so as to drag the chain down a track over the 
ties, the chain being attached to the ship by wire hawsers. 
' The ships weighed 2,735 tons, and the chains (25¢ inches) arranged in two piles on 
each side of ship weighed 36 tons or 1.3 per cent of the weight of the ship. This weight 
dragged 300 feet before checking the ship. The next ship having a little less room to run, 
we increased the weight to about 1.6 per cent of the ship’s weight, which checked the ship 
in 200 feet drag of chain. These chains were not lashed together in a pile, hence only 
300 X 4, or 1200 feet of chain stretched out, were dragging on the first ship, and 200 X 
4, or 800 feet, in the second, which would indicate a lower launching speed on the second 
ship as less weight of chain was being dragged. I regret no record of launching speed 
was kept. The launching ways had 5 inch incline per foot in each case. 
