consumption of fuel for a
moderate increase in the speed, we are enabled the better to
appreciate the large expense incurred in running ocean steamers
sufficiently rapidly for successful mail and passenger purposes. We
will further pursue these inquiries by examining in this table the
consumption for vessels of 6,000 tons, which would make the
displacement of the ship nearly 5,000 tons, such as the "Adriatic,"
the "Vanderbilt," and the "Niagara." It appears that at 8 miles per
hour they would consume 33 tons per day; at 10 miles, 65 tons; at 12
miles, 113 tons; at 13 miles, 144 tons; at 14 miles, 179 tons; at 15
miles, 221 tons; and at 16 miles, 268 tons per day. This is supposing
this speed to be maintained on an average across the ocean, in all
kinds of weather, which this size of steamer could not do without
more engine and boiler power than any of them have. With such
additional power the ships noticed would have scarcely any available
room for freight or any thing else. One thing is very clear from this
table, that when steamers run at very moderately slow rates of speed,
their consumption of fuel is very small; and that when they leave this
low freighting speed, for that of the necessarily rapid mails and
passengers, the consumption increases to an extent and with a rapidity
that would seem almost incredible at first view.

COAL TABLE: No. II.

_The following coal table is constructed in all respects as the
preceding, but for a lower type of vessels, or those whose coefficient
of Dynamic performance is inferior to that upon which the previous
table is estimated. As a consequence, this style of vessel requires
more fuel._

KEY:
A: SHIP'S DISPLACEMENT.

-----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
| SPEED PER HOUR.--NAUTICAL MILES.
A +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
| 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20
-----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
TONS.|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS|TONS
-----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
500|3.95|6.28|9.37|13.4|18.3|24.3|31.6|40.1|50.2|61.7|75.0|89.9|106 |125 |147
600|4.46|7.10|10.6|15.1|20.6|27.5|35.7|45.3|56.6|69.8|84.6|101 |120 |141 |165
700|4.95|7.86|11.7|16.6|22.8|30.5|39.5|50.3|62.9|7