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be added ten thousand more, we certainly
shall be within the mark.

Here, for the present, ends the interesting
report of Mr. Major. Let his exertions be a
lesson to each and all, as to what ONE man
can do, and let every man properly estimate
his power and his duties.

THE ETHER.

WHAT is there in the open space which
intervenes between the earth and the rest of
the planets? What is there in the
immeasurably greater interval which extends in
all directions, right and left, before and
behind, upwards and downwards, between
us, the planets, and the stars called fixed?
Is the gulf which separates one heavenly
body from another, a plenum? that is, is it
occupied, and so far filled, with any material
fluid, however rarified may be its substance?
Or is the said wide gap an absolute vacuum,
perfectly empty of every, the  thinnest, the
most fine-spun expansion or dilatation of
gas; is it void even of matter in a state of
atomic subdivision, in comparison with which
the residuary contents of the receiver of an
air-pump, after we have pumped our utmost,
and can pump out no more, would be regarded
as a medium gross and dense ? Such is the
mysterious question which has vexed natural
philosophers for centuries.

Descartes, and after him Fontenelle,
supposed that the planets were maintained in
their orbits by whirlpools of an extremely
subtle, transparent matter, which, eddying
rapidly round the sun, carried them with it
in its impetuous vortex. Similarly, each
planet had a smaller etherial vortex to
itself, sweeping around its own proper sphere
as a centre, which thus caused the attendant
moon or moons to revolve around their
respective principals. In those days, therefore,
a plenum was the hypothesis in vogue.

Descartes' theory was all the more plausible,
because of the support it received from the
palpable fact that the earth, as well as the
majority of the planets, is surrounded by an
atmosphere. Nevertheless, rational as it
seemed, it was upset by Newton, who made
the sun the seat of a force of attraction, or
a centripetal force, capable of retaining each
planet in its orbit; that is to say, the
centripetal force was exactly counterbalanced
by another force, the centrifugal,—the force
which makes bodies fly off from the centre
at a tangent to the circle in which they
revolve, or rather to obey a law of motion by
continuing to move in,a straight line forwards,
like the drops of water from a twirling mop,
or the splashes of mud from a carriage-wheel.
The sun's attractive force on a planet varies
inversely as the square of the distance of
that planet's orbit from the sun. That was
the law which Newton discovered; but the
source, or cause, or origin of the force,
remained to him a mystery. He only
professed to make use of the word attraction, to
signify generally any force in consequence of
which bodies tend towards each other,
whatever should hereafter be discovered to be the
cause of that tendency. It might be weight,
or electricity, or magnetism, or chemical
affinity; he did not pretend to say what it
was; but his Attraction abolished Descartes'
whirlpools, the firmament was swept clean
of the subtle, all-pervading matter, and the
planetary intervals were reduced to empty
space. Moreover, Newton's hypothesis of a
vacuum was justified by an astronomical
fact, which apparently settled the question in
his favour. The planets, whose proper movement
had been calculated on the supposition,
of the complete emptiness of celestial space,
had always punctually kept the appointments
which astronomers had made for them
beforehand, on the assumption of a vacuum.
The plenum was unanimously rejected on
the faith of an established fact. Vacuum
remained master of the field.

But there is a little comet which whisks
round the sun very rapidly and very
eccentrically, completing its revolution in three
years and four months; it appears in the
heavens like a milky cloud, like a dim
nebulosity through which the stars are seen to
shine without the least diminution of their
brightness. Nevertheless, this speck of white
vapour has a diameter of some twenty-two
thousand miles. It was first observed in
sixteen hundred and eighty-six, and found
again in  seventeen hundred and ninety-five,
in eighteen hundred and five, and in eighteen
hundred and nineteen. Astronomers, noticing
its continual change of form and position,
believed they had discovered four different
comets; but Monsieur Encke, of Berlin,
whose name it now bears, proved that their
observations were simply applicable to four
different revolutions of the same body, and
predicted its return for eighteen hundred and
twenty-two.

Encke's comet did return; but in a
situation where nobody expected it. The same
thing happened in eighteen hundred and
twenty-five and in eighteen hundred and
twenty-eight. A portion of its variation was
caused by the influence of the planets. But
the amount of perturbation due to them is
calculable; there remained another influence
to account for, perfectly independent of the
planets, which led to the discovery, or the
assumed discovery, of one of the most
important phenomena connected with the
mechanism of the heavens. Cautious reasoners
will certainly doubt, and have a fair right to
be allowed to doubt, whether the
superstructure which has been raised on this
observation of the shortened period of Encke's
comet be not of rather disproportionate
magnitude with its basis, a small and isolated
fact. The fate of other deductions and of
previous systems warns us not to shout too