SIDE LAUNCHING OF SHIPS ON THE GREAT I^KES. 99 



clivity of ways, lYi inches per foot; launching weight, 1,170 tons; area of sliding 

 ways, 289.5 square feet; tons, weight per square foot, 4 (will go as high as 9 to 11 

 on large ships) ; time from start to leaving ways, 6.5 seconds; velocity in feet per 

 second, 9.08 feet. 



DISCUSSION. 



The President: — Paper No. 6, entitled "Side Launchings of Ships on the Great 

 Lakes," is now before you for discussion. We will be very glad to hear from any gentleman 

 on the subject. 



Mr. William T. Donnelly, Member: — I just would like to say a word. I had been 

 called upon to design a side launching way myself, and I expected, when laying it down, it 

 would be the first side launching in the South, but I found that brother Stevens was fit- 

 ting out a side launching plant there. Again, the U. S. Steel Corporation, at Mobile, is build- 

 ing a plant with six or eight side-launching ways. I think it would be a matter of great in- 

 terest to engineers who are trying to overcome the difficulties of end launching if they 

 would investigate the side launching, not only as to how it is done, but the actual records of 

 side launchings. I think the records show that the side launching is vastly more safe then 

 the end launching. It certainly affords considerable basis of economy in construction, and 

 the whole preparation for launching becomes vastly more simple. 



The matter of the use of the waterfront is also something to be considered. With end 

 launchings, the waterfront opposite the ways, or the shipyard location, is during the period of 

 launching made inaccessible for the use of any other vessels unless the river is very wide. 



Another factor of much practical importance is in the method of handling material and 

 supplies. Much of the material can be landed on to the ship from the ground or from a 

 floating structure. This is of considerable advantage, with access from both sides of the 

 ship, one from land and the other from water, and it adds much to the expediting of the work 

 in the way of delivering and handling material. 



Mr. Antonio C. Pessano, Member of Coitncil: — The paper by Messrs. Kirby and Hop- 

 kins is a very interesting one, and the authors deserve a great deal of credit for their effort 

 to extend the practice of side launching. The paper, however, rather gives the impression 

 that side launching is only successful in the case of small ships, such as the authors describe; 

 but in order to remove such an impression if it prevails, I might say, for the information of 

 the members of the Society, that we have built ships up to 14,000 deadweight tons, these 

 ships running up to 617 feet in length and 64 feet beam, and we have launched these ships 

 successfully sidewise. 



With respect to the possibility of damage due to side launching, I think it will be of 

 interest to the members of the Society to know that within my own knowledge, covering a 

 period of fifteen years, I have known of at least $150,000,000 worth of ships side-launched, 

 without any substantial claim upon the underwriters. Within the past year our own com- 

 pany has successfully launched over $20,000,000 worth of side-launched ships without any 



