Western courier. [volume] (Ravenna, Ohio) 1837-1838, 1837-06-15

IL sHS tiuo Dc uOW MSu Wdtcf Hhtht ~
any port or harbor, which lies open 70
the ocean, it Will presently subside, and
flow regularly back, for about six hourss
when it will be found al low water.marks
After this, it viii again gradually advances
for six hours, and then return back, in tho
same time, to its former situation; rising
and falling alternately, twice a day, or ia
the space Of about twenty-fcur hours.
/ The interval between its fux and re-
ffux is, however, not precisely six hours,
but about eleven minutes more: SO thap
the time Of high water does NOT always
happen at the same hour, but is about
three quarters of an hour later every day,
for thirty days; when il again recurs as
before. For example, if it be high water
at any place to-day at noon, it will be low
water at eleven minutes after six in the
evening; and consequently, after two
changes more, the time of high water
the next day will be about three quarters
Of an hour; the day following il will be at
about half an hour after one; the day fol-
towing it will be about half an hour after
one; the day after that at q quarter past
two; and SO on for thirty days; when il
will again be found 10 be high water at
noon, the same as on the day the obser-
yation was made. And this exactly an
swers 10 the motion of the moon; she III
ses every day about three quartersof an
hour later than upon.tbe proceeding one;
and by moving in this manner round the
earth, completes her revolution in about
thirty days, and then begins to rise again
at the same time as before.
To make the matter still palmer: sup-
pose at certain place, it is high wafer
about three O'Clock in the afternoon upon
the day of the new moon; the following
day ii will be high wafer at about three
quarters of an hour after three; the day
after that at about half an hour past four,
and so on, till the next new moon; when
it will again be high water about three
O'Clock, the same as before. And by OBJ
serving the tides continually at the same
place, they will always be found to follow
the same rule; the time Of high water,
upon the day of every new moon. being
nearly at the same hour; and three quar-.
ters of an hour later every succeeding
day.
The attractiop of the sun also produ-
ces similar rising and falling of the wa
ter Of the ocean; but, on account of its
distance, not near so considerable as that
which is produced by the moon. 1t will
be readily understood, that according to
the different situations of the sun and the
moon, the tides which are raised by their
respective attraction, viii either conspire
with,or counteract each other,in great
er or lesser degree. When they conspire
together, the tides rise higher, and their
mutual action produces what are called
spring tides. On the contrary, when they
counteract each other; they produce neap
tides.
From slight consideration of what
has been said, we might be led 10 imag-
inc, that the time of high water at any
place, would be when the moon is oyer
the meridian of that place. But this is
by no means the case; it being usually
about three hours afterwards; the reason
of which may be shown as follows: The
moon, when she is on the meridian, or
nearest to the zenith Of any place, tends
10 raise the waters at that place; but this
force must evidently be exertei for
considerable time, before the greatest
elevation will take place; for, if the :
moons attraction were to cease atogeth-
er, when she has passed the meridian,
yet the motion already communicated to
the waters, would make them continue
10 ascend for some time afterwards; and,s
therefore, they must be much more dis
posed to ascend, when the attractive force
Is only in small measure diminished
The waves of the sea, which continue:
after storm has ceased, and almost every
other motion of fluid, will illustrate this
idea; all such effects being easily explain
ed. from the consideration that a small
impulse given to a body in molten, will
make it move farther than il would other
wise have done. tits also, upon the same
principle, that the heat is not the greatest
upon the longest day, but some time af-'
terwards; and that it is not so hot at
twelve O'Clock as at two or three In the,
afternoon; because there is a farther in
crease made TO The heat already impaired.
Instead of its being higher then, when the
moon is upon the meridian of any place,
it will always be found 10 happen, as far
as circumstances will allow, about three
hours afterwards; aud the intervals be-
tween the fiux and reaux, must be reck-
oned from that tmeS in the same manner
as before. sa
The sun being near the earth in winter
than in sim-er, is nearer 10 itin Febru-
ary and October than in.March and Sep-
:. ..,L tLnrof,nr1, tho acrf.nfif st Tides