Scientific American Supplement, No. 446, July 19, 1884 by Various

V >> Various >> Scientific American Supplement, No. 446, July 19, 1884

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From some interesting data which have been placed at our disposal by Mr.
Thomas Schwarz, the manager of the Central Actien-Gesellschaft fur
Tauerei und Schleppschifffahrt, we learn that in the tugs Nos. I. to IV.
the hauling machine develops on an average 150 indicated horse, while in
the tugs No. V. to VIII. the power developed averages 180 indicated
horse power. The tugs forming the first named group haul on an average
2,200 tons of cargo, contained in four wooden barges, at a speed of 41/2
kilometers (2.8 miles) per hour, against a stream running at the rate of
61/2 kilometers (4.05 miles) per hour, while the tugs Nos. V. to VIII.
will take a load of 2,600 tons of cargo in the same number of wooden
barges at the same speed and against the same current. In iron barges,
about one and a half times the quantity of useful load can be drawn by a
slightly less expenditure of power.

The average consumption of coal per hour is, for tugs Nos. I. to IV., 5
cwt, and for tugs Nos. V. to VIII., 6 cwt.; and of this fuel a small
fraction (about one-sixth) is consumed by the occasional working of the
screw propellers at sharp bends. The fuel consumption of the wire rope
tugs contrasts most favorably with that of the paddle and screw tugs
employed on the Rhine, the best paddle tugs (with compound engines,
patent wheels, etc.) burning three and a half times as much; the older
paddle tugs (with low pressure non-compound engines), four and a half
times as much; and the latest screw tugs, two and a half times as much
coal as the wire rope tugs when doing the same work under the same
circumstances. The screw tugs just mentioned have a draught of 21/2 meters
(8 feet 21/2 inches), and are fitted with engines of 560 indicated horse
power.

During the years 1879, 1880, and 1881, the company had in use fourteen
paddle tugs and ten eight-wire rope tugs, both classes being--owing to
the state of trade--about equally short of work. The results of the
working during these years were as follows:

================================================================
| | Freight | Cost of | Degree
| | hauled | haulage in | of
Class of tugs. | Year. | in | pence per | occupation.
| | ton-miles. | ton-mile. |
----------------------------------------------------------------
Paddle | 1879 | 31,862,858 | 0.1272 | 0.686
" | 1880 | 31,467,422 | 0.1305 | 0.638
" | 1881 | 28,627,049 | 0.1245 | 0.537
Wire Rope | 1879 | 15,407,935 | 0.1167 | 0.614
" | 1880 | 17,289,706 | 0.1056 | 0.615
" | 1881 | 17,593,181 | 0.0893 | 0.536
================================================================

The last column in the above tabular statement, headed "Degree of
Occupation," may require some explanation. It is calculated on the
assumption that a tug could do 3,000 hours of work per annum, and this
is taken as the unit, the time of actual haulage being counted as full
time, and of stoppages as half time. The expenses included in the
statement of cost of haulage include all working expenses, repairs,
general management, and depreciation. The accounts for 1882, which are
not completely available at the time we are writing, show much better
results than above recorded, there being a considerable reduction of
cost, while the freight hauled amounted to a total of 54,921,965
ton-miles.

[Illustration: WIRE ROPE TUG BOAT, RIVER RHINE.]

As regards the wear of the rope, we may state that the relaying of the
first rope between St. Goar and Bingen was taken in hand in September,
1879, while that between Obercassel and Bingen was partially renewed the
same year, the renewal being completed in May, 1880, after the rope had
been in use since the beginning of 1876. The second rope between Bonn
and Bingen, a length of 743/4 miles, is of galvanized wire, has now been
23/4 years in use, during which time there have been but three fractures.
The first rope laid was not galvanized, and it suffered nine fractures
during the first three years of its use. The first rope, we may mention,
was laid in lengths of about a mile spliced together, while the present
rope was supplied in long lengths of 71/2 miles each, so that the number
of splices is greatly reduced. According to the report of the company
for the year 1880, the old rope when raised realizes about 16 per cent.
of its original value, and allowing for this, it is calculated that an
allowance of 18.7 per cent. per annum will cover the cost of rope
depreciation and renewals. Altogether the results obtained on the Rhine
show that in a rapid stream the economic performances of wire rope tugs
compare most favorably with those of either paddle or screw tug boats,
the more rapid the current to be contended against the greater being the
advantage of the wire rope haulage.

* * * * *

IMPROVED HAY-ROPE MACHINE.

Hay-ropes are used for many purposes, their principal use being in the
foundry for core-making; but they also find a large application for
packing ironmongery and furniture. The inventor is James Pollard, of the
Atlas Foundry, Burnley.

[Illustration: HAY ROPE MACHINE.]

The chief part of the mechanism is carried in an open frame, having
journals attached to its two ends, which revolve in bearings. The frame
is driven by the rope pulley. The journal at the left hand is hollow;
the pinion upon it is stationary, being fixed to the bracket of bearing.
The pinion gearing into it is therefore revolved by the revolution of
the frame, and through the medium of bevel wheels actuates a transverse
shaft, parallel to which rollers, and driven by wheels off it, is a
double screw, which traverses a "builder" to and fro across the width of
frame. The builder is merely the eye through which the band passes, and
its office is to lay the band properly on the bobbin. The latter is
turned to coil on the band by a pitch chain from the builder screw, the
motion being given through a friction clutch, to allow for slip as the
bobbin or coil gets larger, for obviously the bobbin as it gets larger
is not required to turn so fast to coil up the band produced as when it
is smaller. If the action is studied, it will be seen that the twist is
put in between the bobbin and the hollow journal, and every revolution
of the frame puts in one turn for the twist. The hay is fed to the
machine through the hollow journal already mentioned. By suitably
proportioning the speed of feed-rollers and the revolutions of the
frame, which is easily accomplished by varying the wheels on the left
hand of frame, bands of any degree of hardness or softness may be
produced. The machine appears to be simple and not liable to get
deranged. It may be after a little practice attended to by a laborer,
and is claimed by its maker to be able to produce 400 yards of band per
hour. The frame makes about 180 revolutions per minute, that is, this is
the number of turns put into the twist in this time. The machine can
make a bundle about 200 yards long, which can be removed off the bobbin
without unwinding with the greatest facility.--_Mech. World._

* * * * *

THE ANGLESEA BRIDGE, CORK.

The river Lee flows through the city of Cork in two branches, which
diverge just above the city, and are reunited at the Custom House, the
central portion of the city being situated upon an island between the
two arms of the river, both of which are navigable for a short distance
above the Custom House, and are lined with quays on each side for the
accommodation of the shipping of the port.

The Anglesea bridge crosses the south arm of the river about a quarter
of a mile above its junction with the northern branch, and forms the
chief line of communication from the northern and central portions of
the city to the railway termini and deep-water quays on the southern
side of the river.

[Illustration: THE NEW ANGLESEA BRIDGE, CORK.]

The new swing bridge occupies the site of an older structure which had
been found inadequate to the requirements of the heavy and increasing
traffic, and the foundations of the old piers having fallen into an
insecure condition, the construction of a new opening bridge was taken
in hand jointly by the Corporation and Harbor Commissioners of Cork.

The new bridge, which has recently been completed, is of a somewhat
novel design, and the arrangement of the swing-span in particular
presents some original and interesting features, which appear to have
been dictated by a careful consideration of the existing local
conditions and requirements.

On each side of the river, both above and below the bridge, the quays
are ordinarily lined with vessels berthed alongside each of the quays,
and as the river is rather narrow at this point, the line of fairway for
vessels passing through the bridge is confined nearly to the center of
the river. This consideration, together with some others connected with
the proposed future deepening of the fairway, rendered it very desirable
to locate the opening span nearly in the center of the river, as shown
in the general plan of the situation, which we publish herewith. At the
same time it was necessary to avoid any encroachment upon the width of
the existing quays, which form important lines of communication for
vehicular and passenger traffic along each side of the river, and to and
from the railway stations. Again, it was necessary to preserve the full
existing width of waterway in the river itself, which is sometimes
subjected to heavy floods.

These considerations evidently precluded the construction of a central
pier and double-armed swing bridge, and on the other hand they also
precluded the construction of any solid masonry substructure for the
turntable, either upon the quay or projected into the river. To meet
these several conditions the bridge has been designed in the form of a
three-span bridge, that is to say, it is only supported by the two
abutments and two intermediate piers, each consisting of a pair of
cast-iron cylinders or columns, as shown by the dotted circles upon the
general plan.

The central opening is that which serves for the passage of vessels. The
swing bridge extends over two openings, or from the north abutment to
the southern pier, its center of revolution being situated over the
center of the northern span, and revolves upon a turntable, which is
carried upon a lower platform or frame of girders extending across the
northern span of the bridge. The southern opening is spanned by an
ordinary pair of lattice girders in line with the girders and
superstructure of the swing bridge.

We propose at an early date to publish further details of this bridge,
and the hydraulic machinery by which it is worked.

We present a perspective view of the bridge as seen from the entrance to
the exhibition building, which is situated in close proximity to the
southern end of the bridge.--_Engineering_.

* * * * *

PORTABLE RAILWAYS.

[Footnote: Paper read before the Institution of Mechanical Engineers.]

By M. DECAUVILLE, Aine, of Petit-Bourg (Seine and Oise), France.

Narrow gauge railways have been known for a very long time in Great
Britain. The most familiar lines of this description are in Wales, and
it is enough to instance the Festiniog Railway (2 feet gauge), which has
been used for the carriage of passengers and goods for nearly half a
century. The prosperous condition of this railway, which has been so
successfully improved by Mr. James Spooner and his son, Mr. Charles
Spooner, affords sufficient proof that narrow gauge railways are not
only of great utility, but may be also very remunerative.

In Wales the first narrow gauge railway dates from 1832. It was
constructed merely for the carriage of slates from Festiniog to
Port-Madoc, and some years later another was built from the slate
quarries at Penrhyn to the port of Bangor. As the tract of country
traversed by the railways became richer by degrees, the idea was
conceived of substituting locomotives for horses, and of adapting the
line to the carriage of goods of all sorts, and finally of passengers
also.

But these railways, although very economical, are at the same time very
complicated in construction. Their arrangements are based upon the same
principles as railways of the ordinary gauge, and are not by any means
capable of being adapted to agriculture, to public works, or to any
other purpose where the tracks are constantly liable to removal. These
permanent narrow gauge lines, the laying of which demands the service of
engineers, and the maintenance of which entails considerable expense,
suggested to M. Decauville, Aine, farmer and distiller at Petit-Bourg,
near Paris, the idea of forming a system of railways composed entirely
of metal, and capable of being readily laid. Cultivating one of the
largest farms in the neighborhood of Paris, he contemplated at first
nothing further than a farm railroad; and he contrived an extremely
portable plant, adapted for clearing the land of beetroot, for spreading
manure, and for the other needs of his farm.

From the beginning in his first railroads, the use of timber materials
was rigidly rejected by him; and all parts, whether the straight or
curved rails, crossings, turntables, etc., were formed of a single
piece, and did not require any special workman to lay them down. By
degrees he developed his system, and erected special workshops for the
construction of his portable plant; making use of his farm, and some
quarries of which he is possessed in the neighborhood, as experimental
areas. At the present time this system of portable railways serves all
the purposes of agriculture, of commerce, of manufactures, and even
those of war.

Within so limited a space it would be impossible to give a detailed
description of the rails and fastenings used in all these different
modes of application. The object of this paper is rather to direct the
attention of mechanical engineers to the various uses to which narrow
gauge portable railways may be put, to the important saving of labor
which is effected by their adoption, and to the ease with which they are
worked.

The success of the Decauville railway has been so rapid and so great
that many inventors have entered the same field, but they have almost
all formed the idea of constructing the portable track with detachable
sleepers. There are thus, at present, two systems of portable tracks:
those in which the sleepers are capable of being detached, and those in
which they are not so capable.

The portable track of the Decauville system is not capable of so coming
apart. The steel rails and sleepers are riveted together, and form only
one piece. The chief advantage of these railways is their great
firmness; besides this, since the line has only to be laid on the
surface just as it stands, there are not those costs of maintenance
which become unavoidable with lines of which the sleepers are fixed by
means of bolts, clamps, or other adjuncts, only too liable to be lost.
Moreover, tracks which are not capable of separation are lighter and
therefore more portable than those in which the sleepers are detachable.

With regard to sleepers, a distinction must be drawn between those which
project beyond the rails and those which do not so project. M.
Decauville has adopted the latter system, because it offers sufficient
strength, while the lines are lighter and less cumbersome. Where at
first he used flat iron sleepers, he now fits his lines with dished
steel sleepers, in accordance with Figs. 1 and 2.

[Illustration: Fig. 1. Fig. 2.]

This sleeper presents very great stiffness, at the same time preserving
its lightness; and the feature which specially distinguishes this
railway from others of the same class is not only its extreme strength,
but above all its solidity, which results from its bearing equally upon
the ground by means of the rail base and of the sleepers.

In special cases, M. Decauville provides also railroads with projecting
sleepers, whether of flat steel beaten out and rounded, or of channel
iron; but the sleeper and the rail are always inseparable, so as not to
lessen the strength, and also to facilitate the laying of the line. If
the ground is too soft, the railway is supported by bowl sleepers of
dished steel, Figs. 3 and 4, especially at the curves; but the necessity
for using these is but seldom experienced. The sleepers are riveted
cold. The rivets are of soft steel, and the pressure with which this
riveting is effected is so intense that the sleepers cannot be separated
from the rails, even after cutting off both heads of the rivets, unless
by heavy blows of the hammer, the rivets being driven so thoroughly into
the holes made in the rails and sleepers that they fill them up
completely.

The jointing of the rails is excessively simple. The rail to the right
hand is furnished with two fish-plates; that to the left with a small
steel plate riveted underneath the rail and projecting 11/4 in. beyond it.
It is only necessary to lay the lengths end to end with one another,
making the rail which is furnished with the small plate lie between the
two fish-plates, and the junction can at once be effected by fish-bolts.
A single fish-bolt, passing through the holes in the fish-plates, and
through an oval hole in the rail end, is sufficient for the purpose.

With this description of railway it does not matter whether the curves
are to the right or to the left. The pair of rails are curved to a
suitable radius, and can only need turning end for end to form a curve
in the direction required. The rails weigh 9 lb., 14 lb., 19 lb., and 24
lb. per running yard, and are very similar to the rails used on the main
railways of France, except that their base has a proportionally greater
width. As to the strength of the rail, it is much greater in proportion
to the load than would at first sight be thought; all narrow-gauge
railways being formed on the principle of distributing the load over a
large number of axles, and so reducing the amount on each wheel. For
instance, the 9 lb. rail used for the portable railway easily bears a
weight of half a ton for each pair of wheels.

The distance between the rails differs according to the purpose for
which they are intended. The most usual gauges are 16in., 20 in., and
24in. The line of 16 in. gauge, with 9 lb. rails, although extremely
light, is used very successfully in farming, and in the interior of
workshops.

[Illustration: Fig. 3. Fig. 4. Fig. 5.]

A length of 16 ft. 5 in. of 9 lb. steel rail, to 16 in. gauge, with
sleepers, etc., scarcely weighs more than 1 cwt., and may therefore be
readily carried by a man placing himself in the middle and taking a rail
in each hand.

Those members of the Institution who recently visited the new port of
Antwerp will recollect having seen there the portable railway which
Messrs. Couvreux and Hersetit had in use; and as it was these works at
the port of Antwerp that gave rise to the idea of this paper, it will be
well to begin with a description of this style of contractor's plant.

The earth in such works may be shifted by hand, horsepower, or
locomotive. For small works the railway of 16 in. gauge, with the 9 lb.
rails, is commonly used, and the trucks carry double equilibrium
tipping-boxes, containing 9 to 11 cubic feet. These wagons, having
tipping-boxes without any mechanical appliances, are very serviceable;
since the box, having neither door nor hinge, is not liable to need
repairs.

This box keeps perfectly in equilibrium upon the most broken up roads.
To tip it up to the right or the left, it must simply be pushed from the
opposite side, and the contents are at once emptied clean out. In order
that the bodies of the wagons may not touch at the top, when several are
coupled together, each end of the wagon is furnished with a buffer,
composed of a flat iron bar cranked, and furnished with a hanging hook.

Plant of this description is now being used in an important English
undertaking at the port of Newhaven, where it is employed not only on
the earthworks, but also for transporting the concrete manufactured with
Mr. Carey's special concrete machine.

These little wagons, of from 9 to 11 cubic feet capacity, run along with
the greatest ease, and a lad could propel one of them with its load for
300 yards at a cost of 3d. per cube yard. In earthworks the saving over
the wheel-barrow is 80 per cent., for the cost of wagons propelled by
hand comes to 0.1d. per cube yard, carried 10 yards, and to go this
distance with a barrow costs 1/2d. A horse draws without difficulty,
walking by the side of the line, a train of from eight to ten trucks on
the level, or five on an incline of 7 per cent. (1 in 14).

One mile of this railway, 16 in. gauge and 9 lb. steel rail, with
sixteen wagons, each having a double equilibrium tipping box containing
11 cubic feet, and all accessories, represents a weight of 20 tons--a
very light weight, if it is considered that all the materials are
entirely of metal. Its net cost price per mile is 450_l_., the wagons
included.

Large contracts for earthwork with horse haulage are carried on to the
greatest advantage with the railway of 20 in. gauge and 14 lb. rails.
The length of 16 ft. 5 in. of this railway weighs 170 lb., and so can
easily be carried by two men, one placing himself at each end. The
wagons most in use for these works are those with double equilibrium
tipping boxes, holding 18 cubic feet. These are at present employed in
one of the greatest undertakings of the age, namely, the cutting of the
Panama Canal, where there are used upward of 2,700 such wagons, and more
than 35 miles of track.

A mile of these rails of 20 in. gauge with 14 lb. rails, together with
sixteen wagons of 18 cubic feet capacity, with appurtenances, costs
about 660_1_., and represents a total weight of 33 tons.

This description of material is used for all contracts exceeding 20,000
cubic yards.

A very curious and interesting use of the narrow-gauge line, and the
wagons with double equilibrium tipping-box, was made by the Societe des
Chemins de Fer Sous-Marins on the proposed tunnel between France and
England. The line used is that of 16 in. gauge, with 9 lb. rails.

The first level of the tunnel, which was constructed by means of a
special machine by Colonel Beaumont, had only a diameter of 2.13 m. (7
ft.); the tipping boxes have therefore a breadth of only 2 ft., and
contain 71/4 cubic feet. The boxes are perfectly balanced, and are most
easily emptied. The wagons run on two lines, the one being for the
loaded trains, and the other for the empty trains.

The engineers and inspectors, in the discharge of their duties, make use
of the Liliputian carriages. The feet of the travelers go between the
wheels, and are nearly on a level with the rails; nevertheless, they are
tolerably comfortable. They are certainly the smallest carriages for
passengers that have ever been built; and the builder even prophesies
that these will be the first to enter into England through the Channel
Tunnel.

One of the most important uses to which a narrow gauge line can be put
is that of a military railway. The Dutch, Russian, and French
Governments have tried it for the transporting of provisions, of war
material, and of the wounded in their recent campaigns. In Sumatra, in
Turkestan, and in Tunis these military railroads have excited much
interest, and have so fully established their value that this paper may
confine itself to a short description.

The campaign of the Russians against the Turcomans presented two great
difficulties; these were the questions of crossing districts in which
water was extremely scarce or failed entirely, and of victualing the
expeditionary forces. This latter object was completely effected by
means of 67 miles of railway, 20 in. gauge, 14 lb. steel rails, with 500
carriages for food, water, and passengers. The rails were laid simply on
the sand, so that small locomotives could not be used, and were obliged
to be replaced by Kirghiz horses, which drew with ease from 1,800 lb. to
2,200 lb. weight for 25 miles per day.

In the Tunisian war this railroad of 20 in. gauge, 14 lb. rail, was
replaced by that of two ft. gauge, with 14 lb. and 19 lb. rails. There
were quite as great difficulties as in the Turcoman campaign, and the
country to be crossed was entirely unknown. The observations made before
the war spoke of a flat and sandy country. In reality a more uneven
country could not be imagined; alternating slopes of about 1 in 10
continually succeeded each other; and before reaching Kairouan 71/2 miles
of swamp had to be crossed. Nevertheless the horses harnessed to the
railway carriages did on an average twelve to seventeen times the work
of those working ordinary carriages. In that campaign also, on account
of the steep ascents, the use of locomotives had to be given up. The
track served not only for the conveying of victuals, war material, and
cannon, but also of the wounded; and a large number of the survivors of
this campaign owe their lives to this railway, which supplied the means
of their speedy removal without great suffering from the temporary
hospitals, and of carrying the wounded to places where more care could
be bestowed upon them.

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