le, and should be compared with the logs of _Sirius_
and _Great Western_ as summarized by Tyler. The relatively slow piston
speed and small power put little strain on the moving parts. Tallow
was probably used for lubrication, being introduced into the valve
chest by pots on top of the casing, where radiated heat would melt the
tallow. From the valve chest the melted tallow was carried into the
cylinder, and from there probably passed into the jet condenser. No
doubt the lubricant became a sludge that had to be removed from the
condenser at least once every 48 hours. There is no real evidence
that the engine and boilers suffered any great strains; the operating
pressure of steam must have been low at all times. The boilers were
probably of very low efficiency and made steam slowly. Fuel
consumption was high, and, according to the logbook, the vessel ran
out of coal when she reached the English coast; however, she had
enough fuel left to steam up the Mersey to Liverpool, probably using
wood. At the time she ran out of coal she had used her engine about 80
to 83 hours. While this indicates a fuel consumption of almost a ton
per hour, it must be remembered that the intermittent operation of
the engine required expenditure of fuel to raise steam in cold boilers
over and over again. This was one of the weaknesses in the auxiliary
steamship, particularly, as in the case of the _Savannah_, when the
engine was used a number of times during a voyage without long periods
of continuous operation. Also, there is doubt that the vessel carried
as much as 75 tons of coal; she probably had no more than 55 to 60
tons aboard, if the figure of 1,500 bushels is correct. It is
impossible to establish exact weight-cubic measurements with the
available data.

Though the authorities quoted seem to agree that the _Savannah_ could
steam only 4-1/2 to 5-1/4 knots in smooth water, her logbook credits
her with 6 knots under steam alone at sea. However, this is probably
an approximation affected by current and sea rather than a truly
logged speed.

Judging by references in the logbook, the _Savannah_ carried one boat
on the stern davits. The davits, shown in Marestier's sketch, would
handle a boat of about 16 to 18 feet in length. At sea the boat was
probably carried on top of the deckhouse. The vessel obtained a new
boat during her European trip. It is probable that the lack of
passengers is why a second boat, which could have been stowed on the