The Vancouver independent. (Vancouver, W.T. [Wash.]) 1875-1910, 1880-10-21
The Moons Force.

After getting somewhat accusoomed
to the greatness and strength of bar Of
solid steel l64 #, square, imagine one
which is one mile square, $3.50 #. wide
and as many thick. If it lay on the
ground near the Catskill mountains, its
upper surface would overtop their high
est summit by more than 1000 #. 1t
would be equal to l02, 400 such monster
bars as the last. Its lifting power
would be nearly 240,S69,000,000 tons.
The mind is utterly unable to grasp
such figures. The whole globe contains
100000 00inhabitants. 1feach man,
woman and child could pull with force
of 100 lbs.-a large estimate-to move
such weight would require the united
efforts of the inhabitants Of 1000 such
worlds as this
As I shall have frequent occasion to
speak Of the load which such a bar
could snstain, l shall, for convenience,
call it in round numbers 240,000,0O0,-
900 tons, neglecting the other figures,
because the number is so inconceiyably
great that taking from it billion or so
of tons will alter the result less than
one half Of LIZ. This bar is to he the
unit of measure, which l shall tor the
present employ, and with its help shall
attempt to give some idea of the inhu-
ence of the sun in holding the system
together, and of the attraction exerted
by the planets upon our earth, and by
the earth upon the moon; and, lastly,
by the fixed stars upon the sunand upon
each other.
We begin with the moon because it is
nearest to us, and, with the exception
of the sun, Is to us the most important
of all the heavenly bodies
If a half dozen persons were asked
how large the moon appears, they would
give as many different replies: 1.-THE
size Of cart Wheel" Twelve inches
across" "The size of dining plate;;" Gas
big as mans head" etc. Probably no
one would mention a smaller measure,
yet a cherry held at arms length much
more than covers its disk. 1t is diff cult
to believe that so small body exerts
any considerable influence on the earth
which seems so immensely larger. 1t is
easy to admit that the earth holds the
moon in its orbit; but that to do this, to
bend its course into nearly circular Or
bit, requires any great outlay of force,
is not so clear. Our credulity would be
taxed. we're we asked to believe that the
moon in its efforts to move in a straight
line would break away, although held by
a bar Of steel one #. square, for that
means force able to lif, nearly 5000
tons. An astronomer would grant it,
making first mental calculation to see
if he was justified in doing SO; but even
he would hesitate, and perhaps would
deny that it was possible the moon could
pull asunder one of those great unit bars
one mile square, and equal to more :han
1000, 900 bars each one #. square.
But he would have no hesitation in
saying Impossible :" if told that, rather
than change its course from a straight
line to its present curve, our willful little
satellite would snap like pack-thread not
one, nor two, nor three of those unit oars,
but the united strength Of l0,00-or, in
other words, one gigantic bar whose sec
ton is 100 miles square. Yet mere than
eight such bars, or more precisely, 81 800
unit bars, would but barely defect the
moon into its present path*.
The non astronomical reader may perhaps need 70
be reminded that the moon does not move easily and
naturally IN a crcle-or epse-but that its path, IL
LETT to itself, would be straight nes tangent 10 its
",