The Sun.
London, England, 1848-09-11 00:00:00

S N SEPTEMBER 11, 1848.

THE CORN TRADE.

LIVERPOOL, SATURDAY.—The duty on Wheat has de-
clined to 6s per quarter, and on Flour to 3s 72,-d per
barrel. There is no alteration in the impost on other
articles. We have had another week of highly pro-
pitious weather for the harvest, and the greater propor-
tion of tho grain is now secured in the north of England,
and in good condition. The character of the northern
harvest is likely to be superior to the southern, both as
regards quality and quantity. At our Corn Exchange
yesterday we had a fair show of samples of grain and
Flour. There was a moderate sale for old Wheat to
consumers at an advance of Id to 2d per bushel, and on
bonded the improvement was 3d to 4d per bushel on the
low rates at the beginning of this week. Flour, on the
contrary, was a dull sale, and English sack was easier
to buy. Indian corn was in good demand, and it was
mostly cleared off at is to 2s per quarter advance, 36s
per 4801 b being paid for American, both yellow and
white. Indian meal was 6d per barrel dearer. In other
articles of the trade there was no change from Tuesday,
with small business doing. Prices are maintained to-
day.
MANCHESTER, SATURDAY,--The weather since OUT
last report, although wet for several hours on Tuesday,
and subsequently rather cloudy, has on the whole con-
tinued of a favourable character." The trade, influenced
thereby, as well as the decline in the value of wheat at
most of the leading markets held during the week, has
remained in a state of extreme inactivity, the transac-
tions in nearly every article being confined to the retail
purchases made by necessitous buyers for the supply of
their present wants, to effect which it was necessary to
submit to lower prices generally. At Liverpool and
Runcorn the arrivals of wheat and flour coastwise are to
a fair extent; but of other articles thence or from Ireland
the supplies are again scanty. From abroad the im-
ports of wheat, barley, and Indian corn are on a more
liberal scale, and only moderate of other produce. A t
our market this morning a firmer feeling was apparent
in the trade; and at the reduction accepted during the
week,'namely is to 2s per sack, a fair amount of business
occurred in flour. Wheat must be noted 2d to 3d per
701b,-and oats Id_ per 451 b cheaper; whilst oatmeal, of
which there was but little, either old or new, of suitable
quality offering, sold slowly at barely the previous
currency.

THE ATMOSPHERIC SYSTEM.

IMPORTANT INVENTION.
The failure of the system of atmospheric traction
adopted for two or three years upon the Croydon line,
and recently upon the North-Devon, and its all buttotal
abolition from our railways, must have greatly dis-
heartened those who believed that the invention was
destined to create a new era in locomotion, and that
the time was not far distant when that mode of pro •
pulsion, now almost universal, would be banished
altogether and for ever from the rail ways of the
kingdom. Any pains that were expended in im-
proving the atmospheric mode of traction, one might
naturally think would be lost, in consequence of its
ill. repute owing to the disastrous results, in a pecu-
niary point of view, attendant upon its adoption and
fair trial, so far as we have been enabled to judge
upon the Croydon line. But the enormous ex-
pense, and the fearful and useless expenditure
of power, are generally conceded to be the
cause of the failure of the system heretofore tried,
not the inapplicability of atmospheric traction, if ren-
dered more easy and less expensive of adoption. It is
right, however, to state that the apparent novelty of
propelling carriages by air generated undue prejudice
in the minds of those who chose rather to adopt the
opinions of others, than to take the trouble of forming
one for themselves. The air we breathe seemed so
weak, and untangible an agent, so impotent when
applied to the propulsion of a thousand tons at the
speed almost of lightning, so unmanageable, and so
uncertain in its density, and, consequently, in its in-
fluence, that the promoters of the new system of
traction had other obstacles to contend with than
those which ordinarily attend the first applications of
the best inventions.

It may, therefore, almost be said that the system of
atmospheric propulsion has fallen into abeyance.
It was not, therefore, without some feelings of dis-
trust and misgiving that we inspected on Saturday last
at the Rosemary Branch Tavern, in Peckham, the
model of a railway, worked by a new mode of at-
mospheric traction, which promises, we think, judg-
ing from the experiments we witnessed, to supersede
entirely the old and exploded system of Mr. Samuda,
and :to commend itself, from its vastly inferior cost
and simplicity, to the directors of railways in pro-
gress, but more especially to those who possess short
traffic ; for instance, the Camden incline on the
North-Western, and on a more extended scale on
the South Devon, where its applicability might be
severely tested on the steep gradients. The inventor
seems very desirous to co-operate in a generous spirit
with those interested in other systems, with-the view
of adopting one general and satisfactory plan, an-
swering, in fact, all that is good in the old system, and
eschewing all that has been proved, by practical and
painful experience, to be altogether valueless and costly.
We should state here, perhaps, that Mr. I'iatti, of
Milan, is the inventor, and that it has been patented
in this country by Messrs. Prosser and Ca-rcano.
The plan is thus clearly described by the gentle-
men interested in its promotion, to one of whom (the
gentleman who devoted much pains to indoctrinate
us into the novelty of the invention) we have to
express our thanks :
" A reservoir is filled with compressed air, by
means of a four-horse Cambrian steam engine—a
communication between the reservoir and traction

tube is maintained .by a pipe, and the supply of air
regulated by a cock. The line of rails, which are
eighteen inches apart, is 150 yards long—fifty thereof
being on an incline of 1 in 30—a traction tube is
placed between the rails, of 24-inch bore, giving an
area of a trifle less than four inches. On the piston
being inserted in this tube, and the end of the pipe
hermetically closed, and the coulter attached to the
carriage, which, with its load, weighs one ton—
compressed air of about 301bs. pressure is admitted,
and allowed to exercise its force for only twenty-one
yards. This giies sufficient momentum for its tra-
velling over the remaining line of about 79 yards on
a level, and nearly 50-more on the inclined plane.
" This system is based in the power of compressed
air, acting on a piston, travelling in a series of longi-
tudinal iron tubes, fixed between the usual iron rails.
The upper side of the tube has, in its whole length,
a slot or aperture. The tube is furnished with a lon-
gitudinal vulcanised india rubber valve, which, shut-
ing from within, closes the above slot. The piston
has a vertical coulter, which, passing through the
slot, is attached to the first carriage of the train. At
the commencement of,.and at convenient distances on
the line, are reservoirs, which are filled with com•
pressed air, by means of small steam-engines con-
stantly at work, or by water power when advan•
tageously to be obtained. To set the train in motion
the piston is inserted in the traction pipe, and the
coulter attached to the first carriage ; compressed
air is then admitted from the reservoir into the
traction pipe, and acting behind the piston,
imparts a velocity according to the power
employed, hermetically closing the longitudinal
valve the moment the piston has passed. The com-
pressed air can easily be continued of the same force
the whole of the course. The cocks of the reservoirs
on the line may be worked by the train itself as it
passes. The tube at several sections, according to the
number of the reservoirs, has within it tranverse
valves to stay the passage of the compressed air ;
suspends its action. on the piston when nearing a
station ; and to maintain and determine the commu-
nication from oae tube to the other, and in crossing
the road.
" Numerous advantages are possessed by the At-
mospheric Vacuum Railway over the locomotive ;
viz., immense saving in cost of construction of the
line and maintenance thereof; impossibility of colli-
sions, of trains taking fire, or of running off the rails ;
facility of travelling up steeper inclines, and on curves
of very small radius ; the direct application of the
motive power on the load itself, instead of being, in
a great measure absorbed by the locomotive engine
and tender ; and the consequent ability of drawing
twenty tons more goods every journey, from the
absence 6f the locomotive and tender, usually of that
weight.
Mr. Piatti's system has all the above, as also the
following advantages over the vacuum.
" 1. Perfect closing of the longitudinal valve,
which prevents any escape of air or loss of power.
" 2. Uniformity of diameter of traction tubes at all
acclivities.
" 3. Facility of increasing or diminishing the pro-
pelling power according to the weight of the train.
" 4. Facility of augmenting the speed of the train.
" 5. Facility of surmounting steeper inclines.
" 6. Regularity and precision in the Service of the
trains.
" 7. Saving by the engine and air pumps, being
considerably less, and constantly at work.
" 8. Economy of about twenty per cent. in con-
struction of the line.
" 9. Economy of about twenty-five per cent. in its
maintenance."
This is a manifestat improvement over the vacuum
system, inasmuch as according to Mr. Piatti's plan
of compressed air no waste can take place; the power
is expended in moving the train alone, and not on any
foreign object. Its promoters, who consider that the
engine-houses should be four or five miles apart, in-
stitute the following cemparison between the two
systems :
"TIIE VACUUM SYSTEM.-1. The longitudinal valve,
shutting on the outside of the tube, and having a
pressure of only from two to ten pounds on the
square inch, cannot shut close, consequently much
air gets in, and a considerable portion of the vacuum
is destroyed, and propelling power lost.
"2,3, 4, and s.—As the power, resulting from
the pressure of the atmospheric or external air. (about
eight pounds on the square inch) on the surface of
the piston cannot be increased, it will be necessary
to change the ordinary tubes, and replace them by
much larger pipes and pistons, whenever an increase
of power is required for heavier trains than ordinary,
steeper inclines, or increased velocity.
"6. The closing of the longitudinal valve being
very faulty, a decrease in velocity of the train fre-
quently occurs, and sometimes a total stoppage.
" 7. Large air-pnmps are required to be
the action
worked
by very powerful steam-engines, because th
of the pumps being intermittent, .suh t he_e loss of motivey are inactive
nearly two-thirds of the time. iss
power also takes place, f°
of the longitudinal valve, from
the imperfect closing
which adinits the external
air, and diminishes the vacuum in the tubes.
"8. This system requires the road to be more
levelled than that for compressed air; as also a variety
of tubes and pistons from a diameter of fifteen
inches upwards.
"9. Repairs of road from embankments, cuttings,
&c., to make it more level; also repairs of large
pipes, pistons, and complicated apparatus to valve,
&c., making the working expenses high."
" MR. PIATTI'S COMPRESSED AIR.-1. The longi-
tudinal valve shuts within the tube, and no air can
escape, as the pressure from the compressed air within
the tube of at least thirty pounds to the square inch,
must close the valve hermetically, and prevent any
loss of propelling power.
"2, 3,4, and s.—To accomplish the same objects,
no change of tubes or pistons is requisite—it is only
necessary to increase the force of the compressed air,
which can be done to an almost unlimited extent. It can
also be diminished at pleasure, by admitting smaller
quantities through the cocks, which the train itself
regulates in its passage.