Mr. Biles remarked that there were many advantages in the use of twin screws which had not been sufficiently taken into account.  When a ship with twin screws was being handled in dock there was greater maneuvering power, and therefore less liability for the ship to come in contact with the walls, although, if she did so, there would be greater probability of damage to the propellers.  He thought means could be easily devised of protecting the screws when the ship was in dock.  Another of the incidental advantages connected with twin screws was that smaller engines and smaller propellers were required, and therefore they might run them at a higher speed.  They would also get lighter machinery with twin screws, and there would be less liability to have bad castings and forgings in the smaller engines, and of course the cost would be less.

With respect to the question of the middle line bulkheads, he could not quite agree with Mr. John as to the great advantages of them in a big passenger steamer.  He thought there would be greater difficulty in managing a ship so built if she was in danger of sinking.  Increased subdivision in a longitudinal direction was a very desirable thing, and almost necessary for a condition of immunity from sinking.  In future Atlantic steamers longitudinal bulkheads should be placed not in the middle line, but nearer the sides of the ships, and they should recognize the fact that they had engines and boilers in different compartments, and make arrangements whereby the ship would still float, although the doors in these compartments were kept open.  The proper way to arrive at that was to have a ship with great beam, and to have two longitudinal bulkheads at considerable distances from the sides of the ship, subdivided as completely as possible, both under and above water, so that, even supposing they got water into the space between one bulkhead and the side of the ship, they would have sufficient buoyancy in the other parts of the ship to keep her afloat.  Broad ships must necessarily mean deep ships, in order to have comfort at sea.  They were limited in length, and first came the question how many passengers they wanted to carry.  The experience of a ship like the America—­which was only 400 ft. in length—­showed it was not necessary to go to great length to have great speed.  A ship of 400 ft. to 430 ft. in length, 65 ft. of beam, and with a depth of 45 ft., would be a ship of proper dimensions for the Atlantic trade, and he believed it quite possible to build a vessel of special construction of about 7,000 tons gross register which should steam with less consumption of coal than the Umbria and Etruria at a rate of 22 knots, crossing the Atlantic from Liverpool to New York in six days.  He thought that was likely to be the vessel of the future, and that it would be quite as commercially successful as the Umbria or Etruria.

Mr. J. Campbell remarked that at present the great American liners had only the ordinary compound engines, and he thought that, instead of converting them to triple expansion, they should take a step further at once, and adopt quadruple expansion engines.  This class of engines was being very successfully built in various parts of the country.  He should recommend the adoption of a three-crank six-cylinder engine.