The works of Francis Bacon, lord chancellor of England.

EBB AND FLOW. 529
conjecture what degree of velocity it is proper to and with the hour of reflux on the coast of Africa
ascribe to that motion of the waters, and what and Florida!
distances it may describe in one day. For, if Let it be inquired, how far the hour of tide on
there be selected, in order to form a judgment of the coast of Peru differs from the hour of tide at
this matter, some of those coasts which are less the coast of New Spain; and particularly what
mountainous, or low lying, and which are con- are the differences of the hour of tide at either
tiguous to the open sea, and then the measure of shore of the Isthmus of Darien, in America;
the space of the globe interjacent between the ex- again, how far the hour of tide on the coast of
treme points of the flux and reflux, and that space Peru corresponds with the hour of tide on the
be quadrupled on account of the four movements coast of China?
of the tide each day, and that number again Let it be inquired respecting the largeness of
doubled on account of the tides at the opposite the tides on different coasts, not merely respecting
shores of the same ocean; and to this number their periods or hours. For, although the largethere be something added over and above on ac- ness of tides is generally caused by the deprescount of the height of the shores, which always sions of the shores, yet, notwithstanding, they
rise to a certain elevation above the channel of are closely connected with the true principle of
the sea; that calculation will give the space the motion of the sea, according as it is favourable
which this sphere of water, were it free from ob- or adverse.
struction, and moving in progression round the Let inquiry be made with respect to the Caspian
enveloped globe of earth, would describe in one sea, which is formed by considerable bodies of
(lay, which certainly would not be great. water locked up, without any outlet into the
Now, with respect to that difference which ocean, if they are subject to ebb and flow, and
coincides with the measure of the moon's motion, whatt our conjecture being that the waters ot
and forms the period of a lunar month; we think the Caspian Sea may have one tide a day, not
that the explanation is this, that the period of six two, and such that the eastern shores of it are
hours is not the exact measure of this reaction, deserted by the sea, while the western are over
just as the diurnal motion of any of the planets is flowed.
not accomplished in twenty-four hours precisely, And let inquiry be made, whether the increase
and least of all that of the moon. Wherefore, the of the tide at new and full moons and at the
measure of the ebb and flow of the tide is not a equinoxes, takes place at the same time in difquarter of the motion of the fixed stars, which ferent parts of the world, (and when we say at
is twenty-four hours, but a quarter of the diurnal the same time, we do not mean at the same hour,
motion of the moon. for the hours vary, according to the rapidity of the
waters' motion towards the shores, as we have
DIRECTIONS. said,) but in the same day.
Let it be inquired, whether the hour of the tide Limits. The inquiry is not extended to a full
on the coast of Africa be before the hour of tide explanation of the harmony of the monthly moeabout the Straits of Gibraltar. Let it be inquired tion of the sea with the moon's motion, whether
whether the hour of the tide about Norway is that takes place from a subordinate or a joint
before the hour of the tide about Sweden, and cause.
that, in like manner, before the hour of the tide Relations. The present inquiry is connected
at Graveling! with the inquiry whether the earth revolves with
Let it be inquired, whether the hour of the the diurnal motion of the heavens. For if the
tide on the coast of Brazil be before the hour of tide is, so to speak, the last stage of the gradual
the tide on the coast of New Spain and Floridal diminution of the diurnal motion, it will follow,
Let it be inquired, whether the hour of the tide that the globe of the earth is immovable, or at
at the shores of China is not found nearly the least that its motion is slower by far than that
same with the hour of tide on the coast of Peru, of the water. W. G. G.
VoL. III.-67 2Y