the Navy,
and consequently based the consumption of coal in the table on the
assumption that the mail and passenger vessels generally should be of
as good contractive type as "Rattler." I shall present also another
table showing a much larger consumption of fuel by an inferior type of
vessel. I use these tables because they are thoroughly correct, and
quite as perfect as any that I could construct on the same formula;
and because they carry with them the weight of probably the highest
authority in Great Britain.

COAL TABLE: No. I.

_Displacement,[B] Speed, and Fuel consumed per Day, for Mail,
Passenger, and Freight Steamers, whose locomotive performance is equal
to that of the best class of ocean steam vessels; assuming the
consumption of fuel to be 4-1/2 lbs. per indicated horse power per
hour, equal to 33,000 lbs. raised one foot in one minute. The quantity
consumed is expressed in tons per day of 24 hours._

[B] Displacement refers to the number of cubic feet of water displaced
by the hull; allowing thirty-five cubic feet to the ton.

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
-----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
100|1.04|1.65|2.47|3.51|4.82|6.41|8.32|10.6|13.2|16.3|19.7|23.7|28.1|33.0|38.5
125|1.20|1.92|2.86|4.07|5.59|7.44|9.66|12.3|15.3|18.9|22.9|27.5|32.6|38.3|44.7
150|1.36|2.16|3.23|4.60|6.31|8.40|10.9|13.9|17.3|21.3|25.9|31.0|36.8|43.3|50.5
175|1.51|2.40|3.58|5.10|7.00|9.31|12.1|15.4|19.2|23.6|28.7|34.4|40.8|48.0|56.0
200|1.65|2.62|3.91|5.57|7.65|10.2|13.2|16.8|21.0|25.8|31.3|37.6|44.6|52.4|61.2
| | | | | | | | | | | | | | |
250|1.92|3.04|4.54|6.47|8.87|11.8|15.3|19.5|24.3|29.9|36.3|43.6|51.7|60.9|71.0
300|2.25|3.44|5.13|7.30|10.0|13.3|17.3|22.0|27.5|33.8|41.0|49.2|58.4|68.7|80.1
350|2.40|3.81|5.68|8.09|11.1|14.8|19.2|24.4|30.5|37.5|45.5|54.5|64.7|76.2|88.8
400|2.62|4.16|6.21|8.85|12.1|16.2|21.0|26.7|33.3|41.0|49.7|59.6|70.8|83.3|97.1