The enquirer. [volume] (Richmond, Va.) 1804-1815, 1809-05-23


this district. the securities have been actGaily
f,'ce unified
TO THE ErIroR OF THE ENQUIRER.
siR.
~ In YOUR paper of the 10Th instant !: I
gave demonstration OF the properties of
rotator. wheel along plane, aud general
application OF the same principle to the mo.
ton of the Earth ronRd the Sun, with the
consequences resulting from this motion /
shall now proceed to'investigate and illus
trate these consequences moe particularly
than l did in my last essay although my
professional engagements permit but q very
small portion OF time for such purposes.
am we'll aware of the ridcule generally
attached to those who form new theories and
depart from the established systems of the
scientific world. There is no one more averse
than myself to abandon systems which have
been firmly established upon mathematical
principles. or no one who holds i'm, higher
reverence both the name and works of New
ton VET whenever any other can support
ms doctrines. by geometrical demonstrate
on, shall always be ready to hear him.
In my last essay, / observed thar the We
loeity OF the upper point, was. to the velocity
OF the under point, as twice the chord If the
arch ct the circle over which they might
have moved, to the difference between twice
tile Diameter and twice the chord Of the
supplement- OF that arch !; or halving the
katios, as the chord of the arch If the circle
over which they might have moved, to the
difference between the Diameter and the
chord of the supplement of that arch From
whence without making any other calcula-
ton, concluded tina. when the arch was
nothing, their velocities must be equal but
since after calculating these respective pro
portions in different points of the Quadrant,
Il hnd consequence of very different ma
ture and still mere surprising will result !:
for then the velocity of the upper point will
be to that of the under point as iniinity to
nothing; or in plain terms, that after the
upper and lover points have described very
small arches, the velocity Of the upper point
may be a million of times greater than the
velocity OF the under point. This no doubt
will appear incredible to many, who even
doubted that the upper point of the wheel
goes switter than the under point; to be
told that for certain, although very small
space. the upper point of wheel may move
million OF times swifter, than its CORES
ponding under point. Yet the assertion is
a correct one, and am also warranted in the
same conclusion by a paper. which have
seen on this subject by Professor Blackburn
OF Williamsburgh, a gentleman whose ma
thematical talents hold in the highest
respect.
The under point, therefore, when in con-
, tact with the ground may be considered as
stationary, and its velocity gradually to in
crease until it reaches the horizontal line
when it becomes equal to that of its opposite
point.
When the upper & lower points had each
described thirty degrees, found that the We
n % So l>.xA -.
under point as 5177 to 758. When they had
moved over fortyhve degrees, their velocities
were to each other as 1853 to 1867 and
when they had described an arch of sixty
degrees, they were i'll the proportion OF 0 coo
to 54O4
Let us now apply this to the motion of the
Earth round the Sun On the 21st of March
the sun entered Aries therefore the Earth
was in the opposite point of Libra and as
the Earth revolves round its axis from West
to East, ali those po,.its in the Hemisphe re
next the sun will move slower than the
points OF the opposite Hemisphere; where
fore the gravity OF matter will be most and
the centrifugal force least at noon, on the
| twenty first Of March. Again. on the 22nd
at September the sun enters Libra and the
Earth Aries therefore the gravity of mat
ter will be most &c the centrifugal force least
at midnight On the 22nd of September, or
at noon on that day the gravity of matter
will be least and the centrifugal force grea-
test: The reason of this will readily appear
from examining the second aud third coro!-
laries i'll my last essay.
Wherefore it appears, that from the 21st
of March until the ed Of September, that
particular moment when gravity is most,
has variation of few minutes later every
twenty four hours, and in like manner it has
"A fyNp FL J.cS
Der until the 21st of March.
To calculate the particular hour when
gravity is most for every day i'll the year.
several circumstances must be taken into
consideration. viz: the inclination of the AK
is OF the earth to its orbit her IRE gular pro-
gresslve motion, and the particular species of
cycloid which the earth describes. These
| would lead to calculations which nv present
time does not permit.-But to compare the
effect, which the earth's rotation has upon
the tides, with the effect which the moon
produces, 1t is requisite that these calcula-
lions should first be made, and a table con-
structed, showing the proportion between
the velocity of the points of the opposite
hemisphere of the earth for every day and
hour i'll the year.
In the same manner also as Sir Isaac New
ton has calculated prop. Xxx. Book III. of
the Principia) the length Of the pendulum
for the several degrees of latitude from the
poles to the equator, and the weights of bo-
dies tor these attitudes; so likewise a table