LAUNCHING OF SHIPS IN RESTRICTED WATERS 27 
stern masks having been brought into prominence during the discussion on the 
previous paper, some experiments will be carried out on the Montana model with 
masks of different sizes and shapes. As an example of the effectiveness of any 
means of increasing the water resistance, it may be noted that for the California 
(hull and cradle alone) the value of this resistance at the moment that the ship 
left the ways was 667,000 pounds, or just short of the total normal brake pull on 
the ten brakes. 
DISCUSSION. 
THe CHAIRMAN:—Gentlemen, you have heard this paper, ‘‘Launching Ships in 
Restricted Waters,” which I think you will agree has been interesting, and the motion 
pictures unusually so. 
The question of stopping ships after launching is one of considerable interest. In 
times gone by, our ships have usually been launched in waters where there was ample 
room, without the necessity for elaborate precautions to stop them at a short distance 
from their berth; but with the increasing size of ships this matter has become more and 
more important, and I think the Society is to be congratulated on having such complete 
records presented to it which show the necessary precautions to be taken for the launching 
of these very large vessels, where the launching space is so restricted. 
The paper is now open for discussion. Mr. Gatewood, who has favored us with some 
papers on this subject, will probably be able to give some interesting remarks at this time. 
Mr. Wo. GateEwoop, Member :—I take great interest in the problem of launch- 
ing vessels, and although at Newport News we have unlimited water and do not have to 
restrain our vessels when they are launched, it seems to me that the real trouble with the 
launching of the California was due to the fact that the declivity of the ways was too 
great. I think that when the vessel was clear of the ways there was stored up in it an 
enormous amount of energy, and that it was unnecessary for the purpose of the launching 
to have put into the vessel all this energy. So, if the launching of the California is to be 
a lesson for the launching of other boats, I should say that the lesson would not lie in 
improving the brakes but in so arranging the declivity of the ways that there shall be 
just sufficient velocity to cause the vessel to float, but not sufficient to have stored in the 
vessel as much energy as was the case with this vessel. 
Tue CHAIRMAN :—Are there any other comments? The nature of the paper is not 
such as to lead to very much discussion. 
Mr. H. P. Frear, Member of Council:—At the Union Plant of the Bethlehem Ship- . 
building Corporation, San Francisco, Cal., not very far from Mare Island Navy Yard 
and in waters quite as restricted, many vessels have been launched. Prior to the dredg- 
ing in front of the plant being taken over by the State Harbor Commission, the mud was 
deep and at low tide partly exposed. At that time it was the custom to depend on the 
mud for retarding vessels during launching. As the mud filled in rapidly after dredging 
