The Sun.
London, England, 1835-05-14 00:00:00

EPSOM RACES, 1835.

WEDNDSDAT.
The Woodeot Stakes of 30 sous each, h. ft. ; for two year old colts,
Bst. 61b. ; fillies, Bst. 31b. Last half mile.
Lord Albemarle's ch. c. by Reveller
Sir G. Heathcote's b. f. Piccolina
Mr. Mills's Swallow
NOMINATIONS FOR THE GOLD CUP.
Mr. Carter's Airy, 4 yrs
Mr.. Edwards's Lady Albert, 3 yrs
Mr. Greville's Griselda, 3 yrs, ist
Mr. Gardnor's Messenger, 6 yrs
Atr. Shard's Zittella. 4 vrs
A!, tit's Lucifer, by Lot
t ulouvi Peen c. by Emilius, 3 yt.
Mr. Harrison's Repentance, 5 yrs

I have read the Specification of the Patent for the Pneu-
matic Railway and the accompanying papers, and have also
examined the drawings and models which have been sub-
mitted to me by Mr. Hosking.
Two methods have been heretofore employed for rendering
steam power available in transport upon railways ; one by
causing a travelling or locomotive engine to move with the
load which it draws, the other by constructing, at intervals of
about a mile and a half, stationary steam engines, the power of
which is transmitted to the load by a rope carried along the
road upon rollers or sheaves placed between the rails. The
train being attached to this rope is drawn by the power of the
engines from station to station. The object of the Pneumatic
Railway is to substitute for the rope a partially exhausted tun-
nel,—to employ the fixed steam engines to work air-pumps by
which a rarefaction of the tunnel shall be maintained, and to
cause the trains to be tracked upon the railway by connecting
them with a diaphragm or piston placed in the interior of the
tunnel so as to have that part of the tunnel in advance of the
piston rarefied by the engines, while that part behind the piston
is open to the atmosphere. An effective impelling power is
thus obtained equivalent to the difference between the pressure
of the atmosphere on one side of the diaphragm and of the
rarefied air on the other.
Of the practicability of this project I think there can be
no doubt. The working of large air-pumps by an adequate
moving power, and the rarefaction of air in tubes or tunnels
by such means is not a new idea. It was suggested by Papin
in the latter end of the seventeenth century, and was even
pointed out by him as a means of transferring power to a dis-
tance, without the loss by friction and other causes consequent
upon the use of ropes, or other ordinary means of transmitting
force.---[Papin proposed to obtain an /dive force at one end
of an extended tube by the application of water power at the
other.] It is, in fact, a well-understood principle in physics
that whatever moving force be expended in producing the
rarefaction of air in a cylinder or tunnel, must necessarily be
followed by a corresponding force on the other side of a dia-
phragm moving air-tight in that tunnel, and exposed to the
free action of the atmospheric pressure. In the present case,
supposing the structure of the valvular cord arid the pneumatic
piston to be perfect, the opposite side of the diaphragm will
always be pressed by an effective impelling force, the amount
of which may be calculated upon these principles. It will of
course be perceived that no original moving power is obtained
from the tunnel, or from the rarefied air ; the rarefaction gives
back the power expended by the stationary engines and nothing
more ; and the tunnel must, therefore, be regarded merely as
a substitute for the ropes in the common method of working
railways by stationary engines. But it is evidently attended
with several advantages in comparison with the latter. A
very large proportion of the moving power of stationary en-
gines worked by ropes is intercepted by the resistance from
the weight and friction of the ropes, sheaves, barrels, drums,
&c. All such waste of power is removed by the Pneumatic
Tunnel.
The original expense of ropes, and their wear and tear, would
be likewise saved. Some notion of the extent of this saving
may be collected from the following facts :—when the Liver-
pool and Manchester Railway was about to be brought into
operation, a question arose as to the expediency of working it
by stationary engines, and estimates of the expense were made
by competent engineers. The total amount of capital to be
invested in moving power, was estimated at about 120,000/. ;
of this above 25,0001. was devoted to ropes, sheaves, drums,
and other necessary accompaniments. The total annual ex-
pense of maintaining the moving power was estimated at
42,0001., and of this about 18,0001. was appropriated to the
wear and tear of ropes, sheaves, &c. &c. Thus it appears that
the method of transmitting the power of the stationary engines
to the trains by ropes would absorb about 20 per cent. of the
invested capital, and their maintenance would consume about
43 per cent. of the annual expenditure.
Another source of comparative economy would obviously be
the diminished number of stationary engines. lii the estimate
already referred to, it was calculated that the distance of 30
miles should be divided into 17 stations, with two 40-horse
engines at each station; besides these, there would have been
two engines at the bottom of each inclined plane, one at the
tunnel, two at the top of the planes, and one at the Manchester
end, making in all 42 stationary engines to work a line of 30
miles. Now, according to the estimate of the Patentee of the
Pneumatic ailway, from three to six stations would be suf-
ficient between Manchester and Liverpool, and the whole line
would be worked by frcim six to twelve steam engines. Putting
aside, therefore, the saving of power which would arise from
the substitution of suction in the tunnel for ropes, and sup-
posing the amount of stationary power in both eases to be the
same, it will be evident that a material saving would arise
from the circumstance of that amount of power being derived
from so much less a number of engines,—the number of en-
gine-men, assistants, &c., besides the interest on capital, being
considerably less.

Some notion of the economy of power likely to arise from
superseding the use of ropes may be collected from the result
of experiments made by Messrs. Stephenson and Locke on
the resistance arising from the friction of ropes. They found
that a load of 52 tons drawn by stationary engines worked by
ropes through mile and half stages offered a total resistance
amounting to 1,1561b5. ; of this 5821b5. arose from the fric-
tion of the load, and 5741b5. from the friction of the ropes.
In the case of the Pneumatic Railway, the friction of the rope
is replaced by the friction of the air-pumps and of the im-
pelling apparatus, and it will be evident that the latter, com-
pared with the former, must be almost insignificant. Hence
the power wasted in its transmission from the stationary en-
gines to the load, which in one case amounts to 50 per cent.
of the whole moving power of the engine, in the other is of
comparatively trifling amount.
Slopes on railways will always be objectionable whatever power
be used; for even the most gentle ascent will increase the re-
sistance of the load in an enormous proportion. The difficulties,
however, which they present are materially less when the line
is worked by stationary than by locomotive engines, and would
be still further diminished by superseding the rope ; the re-
sistance arising from the rope being always greater on inclined
planes than on the level, owing to its increased thickness and
consequent weight. A load which requires a 4i-inch rope for
the level requires a si-inch rope upon a slope of 1 in 100.
The weights of equal lengths of these ropes would be in the
proportion of about 2 to 3, the slope requiring one-half more
weight of rope than the level. Besides this, the moving
power on a slope in addition to the ordinary fi iction which it
has to overcome on the level, has likewise to draw up the
weight of the rope,—a resistance which will be increased in
proportion to the acclivity of the slope.
The disadvantages produced by slopes when locomotive en-
gines are used are still more formidable. The same engine
which is fitted to work upon the level is altogether inadequate
for the slopes, the consequence of which is, either that the
locomotive is strained beyond its power by working up the
slopes, and rapidly destroyed, or that the engines must be more
powerful than is requisite for the common level of the road,
and thus power and expense wasted ; or finally that an auxiliary
engine must be kept constantly ready at the foot of each slope
with its fire lighted and its steam up ready to help up the
trains as they arrive. Unless the trains be almost incessant
(which even on the most frequented rail-road they never can
be), this last expedient, which is the one adopted on the Man-
chester line, is attended with great waste of power and expense.
Stationary engines worked on the pneumatic principle would
effectually remove all these difficulties and objections.
The weight of the trains which could be drawn upon the
pneumatic railway, and the speed of the motion imparted to
them, would entirely depend upon the power of the stationary
engines. As the friction or other resistance does not increase
with the velocity, the same absolute expenditure of power
would draw the same load at whatever speed. The high speed
attained by locomotive engines has been attended with great
expense, but this has not arisen from the increased expendi-
ture of power. It has been caused by the wear of the engines
themselves consequent on their rapid motion on the xead, and
by the necessity of sustaining a fierce temperature in the fire-
place in order to be able within the small compass of these
engines to generate steam with sufficient rapidity to attain the
necessary rate of motion. As the magnitude of the stationary
engines would not be limited, and as they would not be subject
to the injurious effects of motion on the road, steam could be
produced in sufficient quantity for the attainment of any re.
quired speed without increasing its cost, or in any way impair-
ing the machinery.
One of the obstacles to the attainment of great speed by
stationary engines worked by ropes is the delay produced in
transferring the trains from engine to engine, and from station
to station. The momentum imparted to them is lost at each
change, and these changes occur every mile and a half, so that
the train has scarcely attained its requisite speed when its
motion must again be checked in order to hand it over to
another engine. This difficulty is removed by the pneumatic
system; there being no rope to be detached and attached the
engine passes on by its momentum from station to station, and
a contrivance is provided by means of a valve at the stations
by which it is brought under the operation of the next engine
without stopping its motion.

Althouglithedanger of accidents to passengers on the pre-
sent railways, worked by locomotive engines is considerably
less than that of travelling by horse coaches on turnpike roads,
yet serious accidents have occasionally occurred. These
have generally arisen either from the locomotive engine run-
ning off the rails,—from one train running against another,--
from the locomotive engine breaking,—or finally from persons
standing upon the rails being run down. In the pneumatic
system there is almost a perfect security from these causes of
danger. From the engines being stationary, and the tunnel
rising between the wheels of the trains, it is evidently impos-
sible for the carriages to run off the road ;. and from the
manner in which the system is worked it is impossible that one
train can run against another. It happens also that the nature
of the rails themselves, forming, as they do, merely ledges
upon the sides of the tunnel, prevents the possibility of per-
sons standing between or upon them.
In railways worked by stationary engines serious accidents
have occasionally neenrr(,d by the ropes breaking while the
train ltns been a,:ceciling a Jul,,. hi such cases the train has
clowit by its weight with u frightful rapidity, producing the
destruction of the carriages and the loss of life. It is evident

It
nthis
vsaonutracueeopfodsasnegs
seerdisbyremovesiy s
tiye
int
above
road deserves to be particularly noticed. In the
road the engines and carriages are kept upon the road by
flanges or ledges raised upon the tires of the wheels, which
press on the interior of the rails. Every thing which' causes
the carriages to press on the one side or the other causes these
flanges to rub against the rails. When a curve or bend hap-
pens in the road, the carriages are guided by the pressure of
one or the other flange on the side of the rail, which of course
is accompanied by considerable friction. In the Pneumatic
Railway there are no flanges, either on the wheels or rails ;
the carriages are guided by wheels or rollers placed in a hori-
zontal position, and acting upon the external sides of the.
channel which receives the valvular cord. By this means all
resistance which arises from what is called rubbing friction is
removed, and every surface which moves upon another moves
upon it with a rolling motion.
It is well known that notwithstanding the prosperous condi-
tion of the Manchester Rail-road Company, yet their expendi-
ture in locomotive power has been so enormous as to cause-
considerable anxiety on the part of the Managers, and some of
them have even inclined to the opinion that the question of
stationary power deserves to be re-considered. This opinion
would probably be confirmed and strengthened, if the practi-
cability of the pneumatic system were satisfactorily demon-
strated by experiment upon a sufficiently large scale.
On the whole, it appears to me, that if the mechanical diffi-
culties of maintaining the Pneumatic Tunnel sufficiently air-
tight be overcome, the system presents a fair prospect of being
practically successful. Theao difficulties are not so great as
they may at first appear. It should be recollected that nothing
approaching to the exhaustion of the tunnel can be necessary ;
nor even any considerable degree of rarefaction. Supposing
the tunnel to have an internal diameter of 40 inches, the im-
pelling diaphragm would have a surface of about nine square
feet. If, in such a tunnel, a de7ree of rarefaction were pro-
duced sufficient to cause a barometric guage to fall two inches
(which would be an extremely slight degree of rarefaction in-
deed), an impelling force would be obtained amounting to
one pound on every square inch of the surface of the diaphragm,
which would give an impelling force of more than half a ton.
It is calculated that on the common Railways the amount of
load is above 200 times the force of traction, and it would .
therefore, follow that this force would be sufficient to draw a
load of 100 tons. If an additional inch of mercury be made to
fall in the barometric guage to balance friction, &c., still the
rarefaction would be extremely inconsiderable, and the con-
trivances to prevent leakage would appear to be attended with
no great mechanical difficulty.
From the various reasons which I have above stated, I ant
of opinion that the present project would, if carried into exe-
cution, be likely to be attended with greater economy and safety
than other method of working Railways now practised ; and I
see no reason against the attainment of as much speed as is ob-
tained by the Locomotive Engines. At all events, having
explained the reasons on which I have grounded this opinion
every one can judge to what weight it may be entitled. The
project would appear to be well deserving of trial on some
Rail-road of limited length, such as that between London
Bridge and Greenwich, where it would be sufficient to have
stationary engines at the extremities. In such a case I see
scarcely any limit to the speed which might be attained with
safety ; and the economy as compared with Locomotive
Engines would probably be very great.

DION. LARDNER.

SPAIN.

CARTEL for the EXCHANGE of PRISONERS.

The following is the text of the convention lately agreed
upon, through Lord Eliot's mediation, as Commissioner
from his Britannic Majesty, for the future conduct of the
civil war :

Art 1. The Commanders ia Chief of the two armies now at:
war in the provinces of Guipuscoa, Alava, and Biscay, and
the kingdom of Navarre, agree to preserve the lives of all
persons taken on either side, and to exchange them as fol-
lows :

Art. 2. The exchange of prisoners shall be periodical—two
or three times in each month, or more often if circumstances
shall require or permit it.
Art. 3. The said exchange shall be in equal proportions to
the number of prisoners which may be produced; and the
number exceeding those so exchanged shall remain in charge
of the party who took them, until another opportunity of ex-
change shall occur. _

Art. 4. Officers of all ranks, employments, classes, and de-
pendencies, shall be exchanged by each party according to
their respective ranks. _

Art. 5. If, after an exchange between the two contending
armies shall have taken place, one of the parties should require:
a position for the security and proper treatment of the prisoners
exceeding those so exchanged, it is agreed that they shall re-
main in the charge and keeping of the party in whose posses-
sion they may be in one or more towns, which towns shall be
respected by the opposite party, who shall not be permitted to
enter into the said town or towns, nor commit any act of hos-
tility against them, during the time the prisoners may so re-
main ; it being clearly understood that in the town or towns
where the prisoners may so remain there shall be no manu-
facture of arms or ammunition, or any other military establish-
ment; and that the town or towns shall be chosen beforehand,
by common consent of both parties.
Art. 6. During the present hostilities no person whatsoever,
civil or military, shall be punished with death for his political
opinions, without being previously tried and 'condemned ac-
cording to the laws, decrees, and ordonnances now in force in
Spain. This condition is to be understood only as relating
to those who are not in reality prisoners of war, those being
provided for in the preceding articles.
Art. 7. -The contending armies shall religiously respect,
and leave in entire liberty, all sick and wounded found in
hospitals, houses, villages, barracks, and other places, pro-
vided there be certificates of the same from their medical at-
tendants.

Art. 8. If the war should extend to other provinces the pre-
sent convention shall be observed in them, as in these pro-
vinces, and the kingdom of Navarre.
Art. 9. This convention shall be strictly observed on both
sides by all the General Officers who may succeed to the com-
mand of the respective armies.
(Signed) TOMAS ZUMALACARREGUI,
Commander-in-Chief of the Army.
Head-quarters, Asarta, April 28,* 1835.
(Signed) GERONIMO VALDEZ,
Commmander-in- Chief of the Army of Operations.
(Signed) ELIOT.
Head-quarters, Logrono, April 27, 1835.
* The first treaty was signed by'Zumala.earregui on the 25th, but
some unimportant alterations having been made by Valdez, it was
recopied, and the second signature affixed on the 28th.

Per Ton

THE MARKETS.

COAL MAR
s. d
17 3
15 3
15 6
19 0
17 6
14 6
16 0
15 0
17 0
18 6
17 0
35 01
21 01
4

,KET.—May 13.

Adair's
Ilensham Main..
East Percy
'l,,bburn Main
Holy well
Ord a Redhugh
Pontop Windsor
Picton
South Hartley
'l'anfield
Wylam
Cannel
I.lanaeimech Coal
Merthyr
Twibbell's Gawbcr Hall
Walls End Bell and Brown l9 :1
Walls End Brown's lB 0
Walls End r hirt, n .. 15 0
Walls End Clark and Co l7 ti
Ships arrived since I

Per Ton
Walls End Heaton l3
Walls End Hilda
Walls End Hotspur . . lB 0
Walls End Killingworth
Walls End Ncw•n►arch lB 6
Walls End Northumberland
Walls End Riddell's
%Va.'s End B addyll's •'l 0
Wa a End Helton
Walls End Lambbm
Walls End Lyons...".
Wes 17n.1 Russel's He-ton 2l (►
Walls End Stewart s .....
Walls End Adelaide
Wa Is End Gordon ......... IS 0
WaLs End South Durham l9 3
Walls End Tees ......
Walls Ead St. Helen's Tees l9

8. d.

COUNTRY C

last market-day, 106

:ORN MARKETS DURIN

THE WEEK.

Wheat. Barley. Oats. Beans. Pease.
Per Quarter. s. to s. Is.tos.ls. to s. s. to s. s. t 3 s.
Abingdon.-- 54 (33) 30 :34 22 30 :38
Andover ...--- 35 <9 29 34 123 33
13;rmingliam---- 50 58 :30 40 16 22 33 --
Bridport 3B s') 32 :36 28 30 • M/
Cirencester ,3f 48 24 n 2 23 27 40
54 63 38 40 26 31 46
Guildford 38 54 28 35 2,3 30 46
Ile nley--
Here fo r d 50 56 23 32 24 27 41;
Highworih 42 60 32 42 28 34 —5;
Maidenhead 50 68 34 44 22 30 36 37
Monniouth.,.- 33 42 29 31 22 30 34
Reading 30 53 22 36 i2B 32 40
Salisbury 36 50 23 28 36 45
Southampton 54 58 33 40 28 32 42
Stroud
Tewke,bury . :36 26 22- 32 40
Uxbridge
Wantage 3O 57 24 30 19 32 34 42 7
Wirminster .3.-- 32 52 28 •30 24 27 34 40
21 22 33
Worm:ter— :30 48 130 32 24 23) 40

- CHELTENHAM MARKED.
Per Bushel. s. (1. to s.d I Pet
Wheat
3 0 39 i Mutton ..
Brley .
Oaats 33 Veal
Beans
Pease 5 0 7 0 Lamb
hay 31. 15s. to 4/. 10s. fd. I,

r ton

LEWES MA RKET.— May 12.
Per Quar Cr. s. d. to s. d. Per Quarter. s. 0. to s d.
Wheat, White ... 40 0 42 0 Oats 2O 0 23 il
"4-.--- Red 36 0 09 0 I Pease 9 4t 0
Barley 3l 0 33 0 Oil Cske...l:!. 4s. per Thousand.

d. tc
6 7
(li 7
I 8
li 7
0