44 STRUCTURE OF VESSELS AS AFFECTED 



Mr. Robinson : — I trust I was not misunderstood as recommending thp substitution of 

 compressed air for any other means of preserving the safety of the ship. I quite agree with 

 Mr. Gatewood in everything he said about subdivisions, care in building, and other means 

 of that character, for preventing the loss of the ship. It was not so long ago that we were 

 told that the Titanic was unsinkable, and that statement had the force of considerable author- 

 ity behind it. It did not prove to be true. 



•My recommendation of compressed air was purely on the basis of a simple additional 

 safeguard — after you had taken all the proper structural precautions, that was the simplest 

 thing you could put on to add to them. 



As to its taking a long time to use it, it is the thing upon which the submarine boats 

 rely almost altogether for most of their operations, and it takes but a fraction of a second 

 to open a stop cock and a very few seconds for the air to come in and blow the water out. 

 If the ship is designed, and the installation put in with that operation in view, I do not think 

 it would take any great length of time to utilize the system. 



Mr. Dickie (Communicated) : — The discussion on my paper (No. 3), "On the Pos- 

 sibility of Building a Large Passenger Liner that Would not, under any of the Known Mis- 

 haps at Sea, Lose her Buoyancy or Stability and Sink," was of such a character as to render 

 any reply on my part unnecessary except to express my appreciation of the very kind way in 

 which my short paper was received by my friends in the Society who took part in the 

 discussion. 



There are some things, however, that were noticed in the discussion that I think it neces- 

 sary to refer to. Naval Constructor Taylor was puzzled about the location of my upper deck, 

 which is just about the middle of the ship's depth of hold. The upper member of this; double 

 deck, as I have shown it, is in the position of the upper deck on the vessel on which I wrote 

 the paper. On that ship we have the poop, bridge and forecastle deck the full length of the 

 vessel, below that the shelter deck, below that the upper deck with the main and lower decks 

 below. In a vessel with six completed decks it may be wrong and misleading to name the 

 third one below the weather deck the upper deck. In some of the new registration books a 

 different deck nomenclature is used : begimiing with the first deck above the inner bottom we 

 have the orlop, lower, 'tween, middle, upper, shelter and promenade. In this case the depth 

 to determine scantlings is taken from the base line to the upper deck and the half girth to 

 the second or middle deck, while the main sheer strake is on the line of the upper deck. 



Some objection was made to my proposed double deck on the score of weight. I admit 

 that the extra weight where I have shown it is not a factor in the strength of the vessel, still 

 both the upper and lower members of this deck need not be heavier than sufficient to give 

 the stiffness required as a platform for the hotel part of the ship, as in the case of flooding 

 no great head of water could ever come upon it. The added weight need not exceed 600 

 tons, a very small percentage in the displacement of such a vessel. 



Mr. Robinson refers to something that nobody had touched upon, "The installation of 

 a compressed-air system." I think that I was the first to use this system in the floating of 

 a stranded ship. Thirty-four years ago the ship Jessie Osburn went on the rocks about eight 

 miles north of the entrance of San Francisco harbor. The bottom was torn out of her and I 

 bethought me of the possibility of floating her on air. The lower deck was tightened and 

 well shored to the upper deck, on which I established a good-sized air compressor with a 

 boiler to operate it. When all was ready the tugs took hold, the compressor was started. 



