The star. (Reynoldsville, Pa.) 1892-1946, 1910-07-13
HOW SCIENTISYSEZPLA
THE RIDDLE OF
THE Tides.

It is said that Newton got his
idea of gravitauon from an apple
which fell and struck him on the
head. The apple simply fell like
stone or any other body might fall,
1t became detached from Its support
and took the shortest path toward
the centre of the earth. Newtons
head interviewed, and hence our
knowledge of those forces which
guide the movements Of the plane
tary system. Newton successfully
applied his idea of gravitation to the
solution of many problems, among
which was the explanation OF oceanic
tides. He showed that these were
principally due to the attraction OF
the moon. The attraction of the
earth holds water on its surface, but
the moon, with the assistance OF the
sun, pulls this out of shape. The re-
sultant distortional effect is exhibited
to us in the form of tides.
Not only are the waters pulled out
Of shape, but the world is itself dis
very, very little, but, all the same, 1t
has quite recently been measured by
DR.. Hecker, of Potsdam. Whether
the world behaves like the indestruc-
tible indiarubber ball which is the
pet dogs toy and yields as a whole,
whether it is only superficial cover
like that of the cored golf ball which
moves, or whether it is the move
ment of a something beneath the
crust of our world which causes the
same to rise and fall as if 1t were
raft actuated by an ocean swell-to
get an answer ask the nursemaid on
the pebbly beach. These changes in
shape of water and land are due to
attractive influences, and twice day
oceans and continents alter their con-
figuration with chronometer-like pre-
cision.
Could we remain stationary at
great height and gaze at our earth
through a telescope with very high
magnifying power, we should see it
both smile and frown. AS it turned
round to face the sun not only would
flowers open and leaves uncurl, but
birds would sing, lamp-posts and
chimneys would straighten up to at
tention, and valleys would expand.
From 10 a. m. to 2 p. m. the place
we were looking at would beam with
smiles! AS this same place turned
away from the sun towards dark
ness, that which was animate would
become drowsy, flowers would close
their petals, lamp-posts and towers
would stand at ease, while valleys
would gently close. The smile on the
earth's face would become frown.
We should have witnessed tide in
organic and inorganic nature.
Weight or load depresses every
surface on which it rests. A man
who leans against lamp-post does
not realize that he defects it. Two
persons standing in the street do not
imagine that they are producing two
overlapping dimples. Were streets
covered with soft rubber they would
readily estimate each others weight.
When the barometer rises over
country it puts on load and a very
big dimple is produced on the sur
face of the same. When the baro-
meter falls the load is taken away
and the normal surface is restored.
This means that changes in baro-
metric pressure give rise to changes
in surface inclination, the ground
slopes downward toward the area of
greatest pressure. If, therefore, we
can measure these changes at the
place where we happen to be located
we are in possession of information
of barometrical effects extending
over large areas.
Now if the changes in the weight
of the atmosphere will produce
measurable reflections, let us ask
ourselves what happens when the
tide rises on coast line Its mass
will attract things while its weight
will depress the bed on which it
rests. When the tide rises in the
Irish Sea it will produce an effect
a man when he sits on a plank sup
ported at it's two ends. The plank
says downward, and so does the bed
of the Irish Sea when it is sat upon
by the tide.
When the tide rises in the Irish
Sea the bottom Of that sea is de-
pressed, and the houses in Liverpool
bow to those in Dublin. What hap
pens in the Irish Sea happens twice
q day in the English Channel and
along every coast in the world where
oceanic waters rise and fall. Lamp
posts come to attention and salute
the rising sun, while cities bow their
heads to rising tides.
That the weight of tide should
produce some sort of an effect has
long been recognized, and calcula'
&C. r,Y,ft do In a