Richmond enquirer. [volume] (Richmond, Va.) 1815-1867, 1817-11-11


| la the same time, gain any additional We
locitv from the two powers acting togo.
there In other words, will the boat ncu,
faster, by the two forces thus aching, than
/ ifit were impeiled BY either Of them Sc
paraiely|
In the present state OF steam boat na, i
CATION. few roblemS, either in mechanics
or hydraulics, are more interesting than
The above. That II has divided the opin-
ions Of the nost iagca'oos hiakers, Is
noways extraordinary, asst Is one oi those
Problems which will adu,it ol'dIflerent So
luiions under different circumstances.
You request of those who may chonse
10 consider this subject, g to throw his ar
sumerls into assmal compass as pos
sible." | shall, therefore, endeavor 10
consider the above question in The most
general manner.
As respects the st:,iical operation DINA
chimes, the quantity OF pressure is AL
"lich concerns ,is hut In considering
mechanically their operations, we are o.
biiged 10 attend TO their distinctions in
kind as their distinction ink;nd is ac-
conpanied by great differences in their
manner oi acting onthe machine. q boat
impelied by steam moves by The power of
impulse rrpeatc'lal certain small intervals
o. lime; tllatis, by the strokes of paddles
or the floats Ola wheel. A boat which is
set IN motion by sails, is impelled by
pressure or continued impulse. When
both these ,oners act together, The effect
produced isNery different from the effect
caused ifeit.er the velocity of the wheel
or the veto, ily of tho wind WAS increased.
II is also to be observed, distinction
should be made between The velocity of
the wind, and the velocity with which a
boat moves by the force of the wind. A
boat which moves five miles ar hour by
sails, | presume would require u wind
blowing at the rate of Is miles per hour.
II the wind itself only had a velocity OF
miles all hour, while the steam boat was
going AT the same rate bV The power of
Wheels, ii is evident the wsid would add
nothing TO the motion OF the boat; for
the sails then would be in the same stu
alton with the floats oian undershotwheel,
moving with the velocity ofthe stream;
no impulse would be made on them; for
in this state the wind could exert no pres
sure on the sails. Bui if the wind has
greater velocity than five miles an hour,
which it must have to move boat FIVE
miles an hour, ii follows that pressure
upon the sails is eXerted at the same time,
that the boat is inpelled by the wheels.
This pressure also eXer.s itself every IN
slant of time whereas the paddles or
floats of the wheels only act at certain
short intervals. A boat acted upon by
both these powers must therefore have
moreyelocity than when impelled only by
one OF them. II, however, the velocity OF
the wind besuch as 10 move the boat G.
qually as the force of steam, the motion of
the boats not increased; for then no I'M
pulse is made by The paddles or the floats
OF The wheel But, fthe wind, OF itself
can move boat swifter than the machi-
merry ofsieam, the wheels, in this case, in
place OF adding 10 the motion OF tiie boat,
will reiard it; for Tie impulse made By
the iioals of the wheel, viii be III the OPP
poste direction. In order, therefore, for
sailsto benefit steam boat, the velocity
of the wind Oughtio he greater than The
velocity OF Tie boat, but notso great as of
itselfto give the boat the same motion as
the machinery OF steam. ~.