their roughness, and to lessen in some degree
the splash of water into the open boat—not
actually to level the rolling billows, but to
allay their wild tossing and breaking into spray.
Whether oil was taken on board the boat for
that purpose we are not told; we only know
that it was thus used, two or more times, during
that eventful 25th of November.

This subject of oil upon the waves is a
curious one. It is by no means of modern
date, either in its knowledge or its application;
and yet there is only an indistinct appreciation
of it amongst us generally. We do not place
it among our every-day truths.

In ages long past, the effect of oil in stilling
the waves was known to many grades of
seafaring men. Pliny stated that the divers
in the Mediterranean and the Archipelago
were wont to take in their mouths a bit of
sponge dipped in oil, and that they were by
this means enabled to remain longer under
water than other divers who were not so
provided. As the diver wants to retain all the
breath he can, and as long as he can, it is
difficult at first to see how the attainment of
the desired object could be facilitated by this
agency; but an explanation soon offers itself.
The object of taking oil into the mouth was to
calm those small waves on the surface of the
sea, which prevent the light from being so
steadily transmitted to the bottom as is necessary
to enable the diver to find the small
objects they search for without delay. By ejecting
a little oil from the mouth, it rises to the
surface, and, spreading out upon it, calms the
waves sufficiently to admit a good daylight to
penetrate through the water. The habit
followed by many fishermen and boatmen gives
probability to this explanation. Dr. Halley
mentioned that he saw some of the Florida
Indian divers remain under water two minutes
at a time; and he proceeded to notice the
effects of a thin film of oil in. facilitating the
divers' work. A century and a half ago the
fishermen of some of the Hebrides were
accustomed, when the sea was getting rough, to tie
to the end of a cable a mass made chiefly of the
fat of sea-fowl, and allow it to dip into the sea
behind the rudder; the oil from the fat exerted
a smoothing agency upon the waves. The
Lisbon fishermen sometimes allay the waves on
the bar across the Tagus, when they wish to
cross, by means of a little oil. During the
siege of Gibraltar in the last century, the British
officers often observed the Spanish fishermen
pour a little oil upon the sea, to enable them to
see oysters at the bottom. Herring-fishers on
the coast of Scotland can see from a long
distance when and where a shoal is approaching;
the water acquires a peculiar smoothness of
appearance from the oil of the fish. Seal-catchers
in the Arctic regions have often observed that,
when the seals eat oily fish (which they often
do), the surface of the sea above them becomes
much smoother than at other parts. The ocean
is often observed to have a peculiar quietness
in the wake of a laden whale ship. This is due
to the small quantity of oil which, somehow or
other, manages to exude from the vessel,
perhaps pumped up with the bilge-water from the
hold. Off some coasts, where fish are speared
instead of netted, a little oil is poured on the
water, to enable the fishers to see their prey
below.

Dr. Franklin, who had an indefatigable habit
of searching out a scientific explanation for
everything that could be explained by science,
resolved to experiment upon this subject of oil
on water. He had read and heard and seen
that oil is thus used, either to make voyaging
more safe and pleasant or to enable the rays of
light to penetrate the water, and he wished to
know the reason why. He first tried a pond
upon a common. Selecting the windward side,
he poured a little oil on the water. Quickly it
spread further and further over to leeward,
until a considerable area of the pond had a very
thin film, which calmed the water in a singular
way. We rather suspect that some error has
crept into the original account of this experiment;
for it is difficult to believe that a teaspoonful
of oil would render half an acre of
watery surface as smooth as a looking-glass,
which is the substance of Franklin's statement.
On another occasion he made a deep harbour
the scene of his experiments. He anchored a
boat at a certain distance from the shore, and
another boat made several short trips out to
windward and home again. In this second
boat a man had a bottle of oil, which he poured
out in a very small but continuous stream
through a hole in the cork. Franklin, seated
in the first boat, watched the effect of the oil,
while others watched on shore. Leeward of the
anchored boat, little or no change was visible;
but out windward the oily track spread far and
wide, preventing the waves from breaking into
ripple, foam, and surf.

The poor Hibernia was not by any means the
first ship, the crew of which had cause to
welcome the effect of oil upon the waves. About
a century ago a Dutch East Indiaman made a
voyage to the East, and fared pretty well until
nearing the islands of Paul and Amsterdam.
A storm then arose, and the captain poured out
a few ounces of olive oil into the sea, to prevent
the waves from breaking against and over
the ship; the plan succeeded, and the ship
went on her way. One of the passengers in
a letter to the Dutch ambassador at the court
of St. James's, stated that the persons to whom
he afterwards narrated this incident were so
incredulous, that the officers and himself signed a
certificate declaratory of its truthfulness, so
hard did it seem to believe the effect of a very
little oil upon a very great sea. Numerous
examples of a similar character are to be found
scattered here and there among the records of
voyages. One of the many trading ships which
ply between Manilla and Singapore had a
singular oil adventure a few years ago. While
on the voyage she encountered a very rough
and unpleasant sea. Suddenly there appeared
a peculiar smoothness of the sea, although
the wind was still blowing, and the ship
advanced favourably for three days over a