and cargo trade from each other is likely to continue or not.  If the answer is yes, then it seems to become an important question, for the present at least, how to build, on moderately small dimensions, the fastest, safest, and most economical passenger steamer, using all the most modern improvements to make her commodious and luxurious, and an easy sea boat into the bargain.  If cargo is still to be carried in the passenger ships of the future, a moderate speed only will be aimed at in the immediate future, and every effort will be devoted to economy of fuel, comfort, and safety, with a fair carrying capacity.  This latter policy is one which may possibly prevail at least for a time, as it has powerful supporters in Liverpool; but he could not help thinking that very high speeds—­higher than we have yet attained—­must eventually gain the day.  He also thought that they were on the eve of important movements, which will indicate what the next step in the passenger trade is to be; for it must be remembered, among other things, that none of our present English transatlantic liners, even the latest, have yet been fitted with the latest modern improvements for economy of fuel or quick combustion, such as triple expansion engines or forced draught.  They must, therefore, be at some disadvantage, other things being equal, compared with the ships of the future possessing them.  The Great Eastern steaming up Milford Haven about twenty-five years ago between two lines of the channel fleet of old—­two and three decked wooden line-of-battle ships—­the whole fleet saluting with yards manned, was a sight to be remembered.  More than this, that ship, with all her mournful career, has been a useful lesson and a useful warning to all naval architects who seriously study their profession—­a lesson of what can be done in the safe construction of huge floating structures, and a warning that the highest flights of constructive genius may prove abortive if not strictly subordinated to the practical conditions and commercial requirements of the times.  The Sirius and Great Western crossed the Atlantic in 1838, and in 1840 the first ship of the since celebrated Cunard Company made her first voyage.  This was the Britannia, which, with her sister ships, the Arcadia, Caledonia, and Columbia, kept up the mail service regularly at a speed of about 81/2 knots an hour.  The Britannia was 207 ft. in length between perpendiculars, and 34 ft. 4 in. extreme breadth, 22 ft. 6 in. depth of hold, 423 horse power—­nominal—­and 1,153 tons burden, built of wood, and propelled by paddles.  In 1860 the Collins Line started in opposition to the Cunard, and, after a series of disasters, collapsed in 1858.  This was three years after the Persia, the first Cunarder built of iron, had been completed.  In 1850, also, the Inman Line was started with the City of Glasgow, of 1,600 tons builders’ measurement, and 350 horse power.  She was built of iron, and was the first screw steamer sent across the Atlantic from Liverpool with passengers,