The herald. [microfilm reel] (Los Angeles [Calif.]) 1893-1900, 1895-01-20
A STUDY Of TIDAL EVOLUTION.
The Dynamic Effect of Tides
On the Motion Of the Earth.
A Consideration of Familiar Facts
From d New Point of View.
The Rhythmic and Fon-rhythmic Pho
nOmena-SomS Valuable
Deductions.

Science associstion last week, by B. R.
Baumgardt, secretary OF the Southern
California Science association and form.
erly secretary of the Oregon Academy
of Sciences Of Portland Oregon:
All phenomena may DO grouped into
two Clssses-those that are rythmic or
periodic in their nature, and these are
constant and uncbanging, that is, do
not increase and then decrease with
regular rythmiG periodicity. To the
first class, which i8 by fer the largest,
belong al the more obvious phenomena
connected with tbs various maniiesta-
tions OF iorCo in nature, such as light,
heat, electricity, sound, motion, etc, as
we'll as those more mysterious ones
which we comprehend under the general
term of lie.
RHYTHMIC PHENO MENA.
The swaying motion OF q Tsod in a
stream, the rustling OF this leaves in q
tree. the pulnation OF the blood in the
arteries and veins Of the human body,
the rise and iall every twelve hours Of
the tides On our seashores, the periodic
maxima and minima every eleven years
of spots on cur primary, the sun, the
accsleratiug ana retarding motions CT
the planets in their celestial orbits, the
inequalities of our eatellite, the pre-
cession Of the equinoXes, that wonder
full wabbing motion of our earth's axis
around the celestial pole in g majestic
orbit requiring 25 900 yeers for its acc
complishment-the oocillating change
of position of the major sxn of the
earth's elliptical orbis-the great cycle
OF the solar system, when, according to
La Grange, all the planetary perturba-
tions shall have compensated each other
and q new cycle commenced. The
wonderful periodical increase and de-
crease OF light in many OF the variable
stars and many other astronomical pheS
nomens are Gll, [ think, typical Illus
trations of the first class, or those that
are decidedly ry thmic in their nature.
NoN-RYTHMIc PHENOMENA.
But ell phenomena are not of this
kind. There are some astronomical
phenomena which. at least in their
broadcast and most philosophical senas,
differ entirely from this class. They do
not increase and then decrease in regu-
lar rythmic variability, and for this
reason differ entirely from the more OBJ
vi0us ones euch as ! have enumerated.
L
your attention for while this evening,
and I hope to be able to chow you that
10 the subject we are to consider we are
really dealing with one OF the most im-
portant factors in the evolution OF our
earth.moon System.
THE TIDES.
all intelligent people who have lived
by the seashors are familiar with the
rise and fall of the sea which takes place
twice in every diurnal rotation of the
earth on its axis. Long ages ago these
tides ceased to be mystery TO man, and
in fact before their theoretical explana-
ton was mathematicalIy explained man
was perfectly acquainted with their ac-
ton, their intensity, their maximum
and minimum, known as spring and
neap, and, most important of all, with
the wonderful fact that in some mystic
rious way these tides were connected
with the position of the moon in relation
TO the sun. Both Pliny end Aristotle
refer to the alliance between the times
of high water and the stage of the moon.
UNIVERSAL GRAvITATIoN.
Not however, until Sir Isaac Newton
in 1887 presented TO the Royal society
HE immortal principles, was it poasibls
for men to understand the abstract
principle of the cause of the tides.
In this celebrated work Newton, in a
measure which makes is seem as if he
was divinely inspired, untolded to the
aatoniahed world the mechanical theory
of universal grsvitation, showing that
every particle of matter in the universe
attracts every other particle with force
which is even proportionats TO the co.
attracting InRssea, and universally pro-
portionate to the square of the distance
separating them.
CAUSE OF THE TIDES.
The moon, therefore, attracts every
particle of matter on our earth, both
cold and LIQUID. The solids, however,
are not enabled TO yield in such G
marked way az the Liquids are; for the
watsra are forced by the moons attrac-
ton to rise bodily toward her to oer-
tain extent, and in this way cause the
phenomenon OF high tide. 1t must not
be forgotten that the solid crust is also
TO certain degree attracted TO the
moon. away from the waters distant
from the satellite, thus leaving the
waters in high wave behind. Thig is
the explanation OF the neap tides. The
intervening pOoAbiOAo bcbWOOA bhO W. v
high tides, that iH, the positions which
are, as it were, in quadrssUre with the
moon, form the Gibbs.
TIDES CHANGE THE EARTH's SHAPE.
Thus, with little reflection, we find
that thu earth is forced through the at
traction Of the moon to depart from the
spherical form and made 40 il were to
bulge out into an oblste ellipsoid, the
major axis OF which keeps forever fol-
lowing the direction OF the moon in her
ceaseless Journey.
CONSTANT ACTION OF THE TIDE.
But some Of you may think certainly
these tides are Of a rhythmic character.
DO they not rise snd fall? Are they not
very pulsRtion OF the ocean, now
strong, now weak. but ever changing
in regular periodic succession? And
have not myself just given the rise and
tall OF the tides &c an illustration Of
rhythmic phenomena? In answer to this
l will simply propoas that we change
the point OF view. No doubt, from
Terrestrial and. therefore, limited stand
point, the tides do appear to be of n
ryhthmical character. But let us rise
from the terrestrial to tho general. to
the truly philosophical point of view.
riaing high enough TO view the whole
globe at q glance or let us. perhaps.
rather view thu axial rotation OF our