The Virginian. [volume] (Lynchburg [Va.]) 1822-1829, 1828-08-11

horse, considered rs machine, Is adi ara
bly, constructed Tor dfaue hi or sustaining wrig
His limbs form an asserblage Of levers, which
n would require volume 10 point out Attend,
however, particularly 10 the formation Of his
shoulders al the place where the neck rises from
tine chest otthe horse the shonlder-blades form
the resting place of his collar or harness into a
slope or inclination and this slope or inclIna-
ton forms IN angle with perpendicular TO tile
horizon of about fourteen or fifteen degrees II
is clear the line his draught should fo, m the
same angle with the horizon--SVhy Because
the horse viii then pull perpendlcularly 10 the
shape of his shoulder, and all parts ofibe shout
der will be equally pressed by the collar
The horse, besides, con idcrrd mechanically
as a lever, has in this inclined draught mann
lest advantage over all obstacles opposed to IT
III comparison with an horizontal draught its
po, er IS IN fact doubled
We are entitled, therefore. 10 conclude that
single-hofse carts are preferable TO teams and
four single horse carts will draw more than when
y"ked to one cart. The rrason-Because in
thelHtor case. three OF the horses must draw no
rIzontally, and therefore in a manner incousis-
tent with their mechanism.
Truth Of this proved by practice. The small
horses uf the north OF En"laud draw larger
weights than the largest wagon horses OF L9n.
don, and go longer stages. The small horses
oil Ireland will draw, common load, ID cm',
while our best wagon horses do not draw, on an
average, more than 10 or II cwt.
In the case ofour eighthorse wagon, at least
six out oflhe eight horses draw inconslsiently
with their mechanism, that much rScrton Is
misappllcd The horses collar IS also drawn n
gainsi his throat, and his breathing interrupted.
cart teams where the horses are not mar
shallfd, As IN wagons, one horse is standing stlIl
While another IS wasting his strength III pulling
HIM forward. One horse leans one way out of
the line Of draueht whilst another is leaning a
contrary way their strength, in short, IS scarce
~ ever united.
hotsc, moreover, has the momentum of his
draue incre ased by having portion OF the
weight o., his back. Hence, low wheels ara not
50 dtsadyantageous as is generally supposed ;
for low wheels obge The line draught to m
cline agreeably 10 the natural dlaught OF the
horse.
To prove that a horse should have something
TO lit in his draught to give that draught It's ut
mast momentum, Mr.. w. mentioned that he had
made the following experiments.
He constructed the model OF four wheeled
ca rage, whose weight was eghty-rwo ounces.
the fore wheels 3 inshes,and The hind wheels
l03 inches. This was drawn a horizontal
board by line over pulley ~ obstacle Ii
inches high was placed hrlore tire fore-yheel,
aud the splinter bar raised on the fuichels SO
as to be even with the top of tho fore wheel.
The line draught was hrnhOti,oniai
When thlugs were disposed, the weight ne
ccssarv T. draw the fore wheels over the obsta-
Gle vas ~ ounces.
On lowering the splintrrbar. so as 10 make
ihe line Of draught TO he from threr-ourIhS the
hcight OF diameter of the wheel, the weight re-
CURED vas only 30 ounces.
By lowering the splinIer-bar still farther, so
rs Ia make the line Of draught from The arle, the
weight required was reduced to "A ounces.
On changing the point of draught To spln-
ter-bar one inch below The axle OF the fore wheel
tbc weight was only % ounces.
Il was hence To be seen, that the disadyanta-
ees Of drawing from above the centrc.ale as the
Sizes Of The respective arcs passing through The
splnter-bar aud the advantage OF drawing from
below the centre, also as the Sines of respective
ares.
Now. as the splinterbar or point of draught
ia plost ID our carriages, is placed about one
eptt he diameter OF the fore wheel above MS
reutr' i, IS evident that fortuitous pressure, q
Ia1. "a one-hiih of whatever weight lies upon il,
Is actually added to the natural weight by this
situation of the point OF draught.
Another course Of experiments was made by
Nj W.dkor-hs fer- several gentlemen well
versed " mechanics, on a wason-ke model,
weighing about los los the fore wheels iept
, inches N diameter, aud the hlnd wheels feet
& inches, with an obstruction placed against the
Two fore wheels of . inches
When the line Of draught was perfectly hori-
zontal, even with the top ofthe fore wheels, it
required 10 draw it over the obstruction weight
o 80 Tbs.
When the direction Of the linz of dtaught
made an angle with the horizon ofsevCn degrees,
by lowering the point of draught six inches
below the Top Of the wheel. the weight re
CURED was AZ lbs.
When the end of the line Of draught was low-
cred, I'LL the direction OF it was at an angie of
eleven degrees with the horizon, it got over the
obstruction with Al lbs
When the end was lowered to the centre of the
wheel aud the line of draught was at an angle
of fifteen degrees with the horizon, the obstacle
was surmounted with 3}1 lbs.
When the end of the line of draught was low
cred to + inches below the centre or axle, so ms
tina, the angle with the horizon was seventeen
degrees, il was drawn over with BOZ lbs,
When it was lowered to one foot and half an
inch below the centre of the wheel, so that the
angle was eighteen degrees, it WAS drawn over
with % pounds.
When il was lowered to l73 inches below the
centre, (bciug only 6 inches above the road,
and exactly level With the height Of the obstruc-
tom the angle nNentv-three degrees, the weight
necessary TO draw it over the obstruction was
p lbs.
These experiment., though made upon so
much larger scale than the former, produced
exactly similar result.
a third experiment with n common chaise,
when drawn by a spIinter-bar as high as the top
of the fore wheels proved that 1t required 50
lbs. 10 put it in motion; when drawn from the
axle, II required only 81 lbs
With another chaise aud the splinter-bar
three-fouths of the height OF the wheel. the
draught over AN inch nbstuction, required
100 lbs but when drawn from the axle, only 81
lbs.
With another chase, and the splnter-bar
three-iourths of the height of the fore wheel the
draughi over an inch obstacle required ! 10 lbs :;
but when drawn from the axle, only % lbs. So
that in both eases there was one, fourth in favour
of the dianght from the axle.