It will thus be seen that from the 15 days' passage or thereabout, of the earliest Atlantic steamers, we had got down in the days of the Scotia to about 9 days; in the Britannic to 81/4 days, and, at the present time, we have got to 61/4 days, with seven ships afloat that have done the passage under seven days, and capable of making their average passages range between 61/2 and 71/4 days. Ranged in order of gross tonnage, these eight vessels stand as follows: TABLE II. 1. City of Rome. 8,144 2. Oregon. 7,375 3. Aurania. 7,269 4. Servia. 7,212 5. Umbria. 7,129 6. Etruria. 7,100 7. Alaska. 6,586 8. America. 5,528 Here the America shows to advantage, for while being eighth in size she is fourth in point of speed, and from what the author can learn, although he had no authenticated details on the subject, he believed she is economical in coal consumption. He might perhaps be permitted to say that one of the most difficult subjects in connection with the propulsion of ships on which to get absolutely accurate data is that of coal consumption. The records of six to eight hours' trials for the purpose of ascertaining the coal consumption are absolutely worthless, as all shipbuilders and engineers know, and so far as English ships are concerned they are never attempted. Foreign owners frequently stipulate for such trials in their contracts with English shipbuilders, and get wonderfully economical results on paper, but the fact that the trials only extend over a few hours renders them valueless, however carefully the coal may be weighed during that period. An authentic record of the absolute quantity of coal consumed, say by each of the eight fastest Atlantic liners, together with their average indicated horse power on the voyage, for a series of voyages, would be extremely valuable. He gave, in Table III., the consumption per indicated horse power per hour for a number of ships. This table affords valuable data, for it gives, in addition to the dimensions, the moulded draught of water, the midship area, the displacement, the indicated horse power, the speed on trial, the coefficients for the lines both from the block or parallelopipedon, and also from the midship section prism, together with the length and angle of entrance obtained by Kirk's rule, the Admiralty displacement coefficient, together with the coal consumption per day and per indicated horse power per hour. [Illustration: Fig. 3--OREGON.] This table, as will be seen, contains some of the most important of the Atlantic liners, and also a number of other typical ships, which will add a variety to its interest and a value to it. The coefficient, which is contained in the thirteenth column of the table, viz.: Dis 2/3 x speed cubed ------------------------- I.H.P. x sqrt(entrance.) --------------- 10