Weekly national intelligencer. [volume] (Washington [D.C.]) 1841-1869, 1852-08-28


body moves perpendcuary to her horzon and uniform
and rectilinear motions be produced BY art only
when the moving body supported by some plane surface
which it constant force c0ntnuest to act up
moving bodies after ii has set them in motion, causing
them to faster and faster every moment and this
is called accelerated motion. II it increases equally in
equal times as that Of body falling towards the earts
centre Is increased its motion said to be uniformly
celebrated and, if its motiop be equally diminished in
equal times as is that Of ball shot towards sarin the
zenith, it is said to be uniformly retarded. NJ w
- - ss "a ssss u: MI os shi
ldnSsa ~ ~ uniform presi y ~ III The eeerity Of
sy wss sas &
form by the constant resistance Of the water IN wh
they move which also in proportion the square
of their veocities Motion produced by seamis regua
ed by governor, which regulates both the intensity o
the fire and the quantity Of steam desired to act to the
motion desired and where perfect uniformity OF motion
in machinery is unnecessary is regulated by increasing
or diminishing the amount Of work to be performed.
When an impusiye and constant force acts naturally
upon body conformity and simultaneous, IN angular a.
rectons they produce curvinear molten around the cen
tire from which the constant force emanaes ana the
which the moving body describes is either hyperbola,
parabola if the is reenterng one, an epse
circle, according of the forces predomnates
equals the other. The simplest easily percep-
BILE demonstration of curvilnear motion is produced by
whrng weight, tied end Of string while the
other end is held fast in the hand around ones head 1t
will then be observed that the weight exers constant
tendency fly off drawing the hand towards it, which
increases with the celebrity with which the weight whir
ed and if the string break slip from the hand, the
weight will fly off in straight hne called tangent TO
the in which it moved This tendency to hy of is
called its centrifugal (centrehying) force and the force
with which the hand holds the string is denominated the
centpeal centreseeking force and though these two
forces unequal in different parts OF the bodys orbit
Except when that orbit is circle their respective ag
mt fnr pach
the re-entering 1t will also be observed
that the weight in notion the hand itself must
first be moved in curviinear and then IN recprocat-
ing direction which shows that the weight moves IN an
eiptical orbit and consequently, during one-ha OF
each revolution the centrifugal force predomnaes over
the centripetal and vice during the other half
while at two points of the orbit when the weight is
eouidstant from the centre its orbit these two forces
balance each other Here also the prolectie as well as
the centrpetal force must be constant because the
weight is continually attracted by the earth anu ts motion
resisted by the atmosphere but there are no such oota
ces orbial motion in natures works and therefore,
the mpulsve force there constant the planets mo-
ton would be constantly augmented till 1t overoalanced
the suns attractive power when they would rush from
their orbits and run lawless through the skies
The velocity Of moving body may he found by divd-
ing the distance 1t passes over In gwen tune oy tnat
time or by dividing which impelled H. the
force with which would strike another body 1.-THE mo-
mentum by the weight Of the moving body and the mo-
is found by multiplying the velocity BY the weight
of the moving body Therefore, If two bodies, Of equal
weight be impeed by the intensity OF force, the
lighter will with the greatest velocity Consequent
~ if balls, of unequal weight were connected
by chain and then fred from the lighter would
move the fastest and break the chain being held back
by the heavier would revolve around this latter drawing
it gently towards ITSELF till both revolved around their
common centre Of gravity, which would then move IN
straight line influenced only by gravity ana the resistance
! Of the atmosphere.
Now in the case Of the string and weight the impulse
is communicated the weight by the hand and the
mentum generated by this impulse is manfestly decom-
into otwof
moving body would strike obstacle IN Its orbit and the
centrifugal force Of the and the sum of these two
forces is only equal to the motive force rst TO
set the body in motion; for the hand just balances
the bodys tendency fly from its orbit and its velocity
in that orbit is consequently as much less than It would
be in straight line, the centrifugal force or that eI
erted by the hand would communicate TO the body
at rest acting alone The following example will illus
trate this last paragraph:
BODY near the earths surface falls from height of
nearly l6 LIZ feet and this is the velocity produced by
the force Of gravity Now If the earths diameter be
900 feet and multiply this number by the force
of gravity and extract the square root from the produc
shall have % 920 feet omitting decmals which is the
velocity body revolving around the earth 4OIo LIZ
feet from its centre must have per second that the
force Of gravity may exactly balance the centrifugal force,
and the body become q satellite TO the earth Supposlng
this satellite weighs FIVE TONS and multiplying % 92o
and also 10 1l2 feet by have the proportion Of the
momentum in the orbit to the centrifugal force, as
12 600 is so 5l2 tons, the former is nearly lol2
times that Of the latter Again adding these two last
4
tum and dividing this by 5, we have 25,936 ll2 feet,
the velocity Of the body IL we're propelled By the
same force in straight line. asaitnsst 3.N
According to the fourth law Of motion, body cannot
impart greater momentum to another body, or yield
more motive force than that which seit in moton other
wise ii must be conceded that nanmae matter
itself and thereby generate mechanical force which abb
surd being contrary to all experience Those who doubt
the correctness Of this illustration its applicability to
machinery, ought consider that these the known
laws which regulate the motions OF all celestial bodies,
and by which all astronomical calculations made, and
they therefore be true, their almanacs could not
be that these laws have been instituted BY an on
nscen and omnipotent Creator who wisely excluded all
passive forces from His works which they cannot do and
that the force of gravity necessarily be part Of the
aggregate momentum Of the moving body and must there
fore deract from its recnear velocity the precise amount
Of velocity with which would fall towards the earths
centre IL the centrifugal force were suddenly
1t is true that both the orbal and centrifugal FORCES
increase pari passu with the increase OF velocity IN tne
orbit as is expermentay proved By the bursting OF
rrindstones and casron balance wheels when In 700
rapid notion throwing of pieces with momentum sum
Gent to demolish solid walls But then the original me
tye-power which them in motion must have been equal
10 the momentum with which these pieces struck the
walls and when they became separated from the rest
tbev were thrown off with the momentum they had in the
orbit plus the centrifugal force As nechanicans must
lose either the centrifugal force or the orbsl momentum
f their machines in addition to the loss by passive forces
tbev can never realize much available power with any
mocb;ne as they are compelled to employ in setting in
,nt;op At Ars and as the orbita momentum is always
much greater than the centrifugal force would II not be
preferable TO continue using the former and neglect the
latter. in the old way? H. X. SCHErIEKLf.
/ Howell, MICHIGAN