Mat 22, 1914.

THE COLLIERY GUARDIAN.

1121

had absorbed 13’1 kilogs. (28| lb.) per cubic metre, at a
cost of 1’57 mk. (Is. 7d.).

'Meister Lucius and Bruning (Mykantiri) Process.—
Mykantin consists of 24 per cent, of dinitrophenol salts,
36 per cent, of lignin sulphonates and 40 per cent, of
water and impurities, and is employed by brushing it
over the timbers (these being afterwards dipped in the
liquor to make sure of proper coating). The consump-
tion of liquor was 7 kilogs. (15j lb.) per cubic metre, and
the cost 0’28 mk. (3M.).

Trials were made with subjecting the timbers to dry
heat (250-300 degs. Cent, in a chimney flue for two
hours), some of them being then dipped in a 10 per
cent, solution of water glass, and the others in a similar
solution containing 67’5 per cent, of lime. In the former
case, 32 kilogs. (70 lb.), and in the latter, 18 kilogs.
(39Jlb.)were absorbed, the cost being 0T8 mk. (2Jd.)
and 0’01 mk. (Id.) respectively per cubic metre.

In addition to the cost of material, as given above,
the impregnation of pit timber by the vacuum and
pressure processes is attended with the following charges
per cubic metre: Wages, 0’80 mk. (lOd.); steam, 0’10 mk.
(IJd.)—or 0T5 mk. (2d.) for prolonged vacuum and
pressure treatment; depreciation, 0’45 to 0’50 mark
(5Jd. to 6d.). For the simple dipping processes the item
of wages amounts to 0 50 mk. (6d.), and the interest
and depreciation to 0’05 mk. (fcl.), except where the
immersion is prolonged for several days, in which
circumstances this last item must be increased to
0’20 mk. (2Jd.) per cubic metre.

The treated timbers have been distributed to several
collieries, and will be set up in places where no roof
pressure is expected. They are to be inspected by the
committee, and their condition reported upon, at the
end of a year, specimens being removed and tested for
their degree of inflammability, &c., and physical condi-
tion. After five years other specimens will be examined
in the same way, and if any be found to have rotted
between whiles, their working life will be recorded and
the causes of putrefaction investigated.

APPROVED SAFETY LAMP GLASSES.

The Safety Lamps Order of March 16, 1914, contains
particulars of new safety lamp glasses that have been
approved by the Home Secretary.

Brief details are given below :—

Dimensions.

Brand.

Makers.

Ext. dia. Height

ROCO.

Glastechnische Werk-
statten, Dusseldorf,
Oberkassel (Bishop &
Co., 63/4, Bartholomew-
close, E.C.).

mm. mm.

56|-55|... 671-66f

Patterson and
falgar-street,
tle-on-Tyne.

Co., Tra-

Newcas-

62-55 ... 70-55

FIRMTTS. w- E- Teale and Co. 72-50 ••• 70-50
Limited, Swinton.

Wolf Safety Lamp Co., 72-50 ... 70-50
Sheffield.



S. Reich and Co., 15, 72-50 ... 68-55
Clerkenwell-road, E.C.

Ackroyd and Best Ltd., 56|-55|...67i~66|
Morley, near Leeds.

Johnson and Jorgensen 60-55 ... 70-60

Limited, 26-7, Farring-
don-street, E.C.

In each case the permissible variation in thickness is
between 6 mm. and 4 mm. In the case of the third
glass mentioned, when used with an outside protecting
glass they may be made in sizes ranging from 3 mm. to
1mm. in thickness ; and in the case of the fifth, under
similar conditions, ranging from 3^ mm. to l|mm. in
thickness. In any one glass the variation in thickness
must not exceed 1 mm. The ends of the glasses must
not be out of parallel to an extent of more than J mm.

Personal estate of the gross value of .£224,954 has been
left by the late Mr. David Sturrock, of Kelvinside, Glasgow,
and of Clentirran, Kippen, N.B., who controlled the Carn-
tyre Iron Company and the Carntyre Bolling Mills and Iron-
works, Parkhead, Glasgow.

Modern Developments
in Hydraulic Stowing.

SUGGESTIONS FOR APPLICATION IN
BRITISH COLLIERIES.

From a paper read before the Manchester Geological and Mining Society.

By J. DRUMMOND PATON.

Deeper mining; the recovery of seams of coal under
cities, rivers, public institutions, railways, and surface
water; the exhaustion of the best coals; and the need for
greater care and economy in working the thick seams,
are matters that are forcing the question of hydraulic
stowing on the daily notice of mining engineers.

When discussing this subject with British engineers,
the question of roof and floor has continually cropped
up, and the whole system of hydraulic stowing has some-
times been dismissed as hopeless, because of the
crumbling tendencies of certain seams, and their well-
known “ boiling ” tendency when the slightest trickle
of water comes into contact with them. There are
hundreds of mines in this country with better roofs and
floors than those in which some of the finest stowing
installations have been set up in Germany, so that it
needs but the pioneering influence of one or two good
British examples to make this system as popular here
as it has become on the Continent. When the writer
mentions that the man in the hopper house at the surface
in Continental mines is now able to control his mixture
of water and material by the “ sucking ” sound of the
down pipe, and can virtually anticipate the instructions
from the stowers underground as they come to him
over the bell or telephone by the nature of this hissing
and gurgling sound, it will be evident that the process
has entered the province of the mechanic.

A technical objection to the introduction of the method
can hardly now be advanced, but in the writer’s
opinion the chief reasons are the apparent impossibility
of securing sufficient quantities of stowing material—
the excessive wear of the pipes, and the difficulty of
clarifying and lifting the stowing water. These apparent
objections can, however, no longer be upheld in the light
of modern technical advance.

Stowage Materials.

Blast furnace granulated slag is an excellent stowing
material, and if sufficient of this slag is available, the
mining engineer need not care about other sources of
supply. A typical case of this kind is the hydraulic
stowing plant of the Gewerkschaft Deutscher Kaiser at
Hamborn, near Duisburg. At the individual plants of
this colliery, which are connected by their own lines
with their extensive ironworks, 1,800 to 2,400 tons of
granulated slag are stowed per day, and are conveyed to
the filling hoppers by specially constructed self-
unloaders. The great difficulty, however, to the mining
manager is where his shaft is not adjacent to a smeltery.
When the available dumps are exhausted, the first
thought will be to obtain the necessary material from
some adjoining spot along the existing railway lines.
But this may not be easy, as the railway carrying powers
may be taxed to their utmost with goods, etc., unless
an extension is made to the tracks or the colliery com-
pany lays its own lines. When investigating this matter
the writer approached several railway companies with a
view of getting some idea of transport charges, and also
of investigating natural resources for the supply of this
material. It is well enough known to many of the
members that in and around the chemical area of St.
Helens and Widnes there are ready to hand millions
of tons of various materials that are ideal for stowing
purposes. If the writer may prophesy the future desti-
nation of these same dumps, he would say that they
will find a final resting place in the southern section of
the Lancashire coalfield. The writer has outlined two
points where he can conceive of central systems being
arranged by a “ pooled ” arrangement of collieries for
the supply of stowing material, in particular the region
lying in behind Horwich, which is at no very great dis-
tance from the principal network of collieries. Another
proposed stowing material centre is in that portion of
the Lancashire coalfield lying towards Liverpool. In
both of these centres the stowing material would be
collected in wagons, which would return, in the first
case, from the North Lancashire area, after the coal
had been delivered to the numerous cotton mills and
industries, and in the second case from the Liverpool
docks. It might be of interest to the members to know
that the railway companies in Lancashire are distinctly
interested in the hydraulic stowing process, and the
writer can assure all concerned that if in the future any
combined movement is made on the part of the collieries
with a view to establishing a scheme as herein fore-
casted, they will find interested hearers in the directors
of the local railway systems.

It might be well, in this connection, to say a few
words with regard to the densely populated coal district
of Upper Silesia, the so-called “ birthplace ” of the
hydraulic stowing method. On account of the prevail-
ing conditions, the boards of the State collieries (“ Koe-
nigin Luise Grube,” in Zabrze, and “ Dellbruek and
Rheinbaben shafts,” in Bulschowitz, in Upper Silesia)
decided to connect, by means of their own railway line,
the two collieries with a big sandstone quarry about 15
kilometres distant. The daily output of this plant is
5,000 cubic metres. The out-of-pocket expenses (that
is, quarrying, including transporting) amount to 6d. or
7d. per cubic metre for a distance of about 15 kilo-
metres. This example has been followed up by others
—for instance, the Count Ballestream pits (Karstellenge,
Brandenburg, and Wolfgang), and the Hedwigwunsch
and Ludwigsglueck pits of the firm of A. Borsig. The
annual output of stowing material from the plant

installed at these collieries is for the present estimated
to be 2,000,000 cubic metres. Large tracks of land out-
side the industrial areas have been purchased for feed-
ing the mines with material, tracks have been laid, and
it is assumed that other collieries will combine and also
receive their stowing material from this quarry by rail-
way lines yet to be built. This combination of various
collieries for the purpose of obtaining stowing material
at very cheap rates is well worthy of emulating in this
country.

Conveyance of Material.

The building of railway lines for conveying the
material may not, however, be the most economical
scheme. In some districts aerial ropeways and the like
may be found to be much cheaper. The writer is
informed that such a ropeway line exists in the Saxonian
coal basin near Zwickau, built for the Ore • Mountain
Black Coal Company (Erzgebirgischer Steinkohlen-
Aktien-Verein). The length of the ropeway is about
2,800. metres. It may safely be assumed that with a
modern aerial ropeway plant 500 tons and more per hour
can be conveyed from 10 to 20 miles (at 1’5 pf. (3-16d.)
per ton-mile, or 1 pf. (|d.) per ton-kilometre), after
taking into consideration the total working costs, but
excluding depreciation and interest. Mention may also
be made of the sand quarry of the Steinkohlen Berg-
werk (Black Coal Colliery), “ Neumuehl,” near Gewerk-
schaft Deutscher Kaiser, which is about eight kilometres
(5J miles) distant from their stowing pit, and connected
with it by a narrow gauge line. Small self-unloaders
drawn by small electric lomomotives are in use with
overhead wiring. The capacity per hour of this plant is
100 cubic metres. It will also be of interest to mention
that the Verein fuer Bergbauliche Interessen (Associa-
tion for Mining Interests) of the Higher State Mining
Board of Dortmund has made an application to the
State Minister to grant rebates for the conveyance of
stowing material on the Rhine-Herne Canal, which
crosses the whole Rhenish Westphalian coal district,
and is now nearing completion. This example may
extend the field of the Manchester Ship Canal and
similar undertakings.

Wear of Piping.

The writer now deals with the second point, namely,
the important question of piping, which has been the
bugbear of most of the stowing plants. There are three
sorts of piping which require consideration, as follow :—
(a) The unlined mild iron pipe; (5) the porcelain lined
pipe; and (c) the iron lined ovoid pipe. The first-
mentioned pipe is the best for use where the material to
be flushed is small, and the consequent wear trifling.
Practice has demonstrated that this kind of pipe, in
similar circumstances, has a longer life than the steel
pipe, and owing to its particular structure the mild iron
pipe is only slightly affected by the current of material,
whereas in the case of the steel pipe, in consequence of
its grainy structure, the wear is rapid. How small the
wear can be with a mild iron pipe made of material eight
to 10 millimetres thick is shown by the fact that at a
trial at a Rhenish colliery with various types of piping,
the amount of wear in the mild iron pipe was only 3*5 to
5 millimetres after the passage of 60,000 tons of granu-
lated blast furnace slag. This class of pipe is manufac-
tured with loose flanges, so that it can be turned several
times before it is quite worn out. This shows that when
small quantities of material of sufficient fineness are
flushed, even unlined piping may be used for quite a
long time.

More important becomes the question of wear when
large quantities are considered, say, 3,000 to 5,000 cubic
metres per day, as is the case at one of the Upper
Silesian collieries, and also in the Rhenish Westphalian
and Saxonian district. In this case lined piping must
be employed. The extremely high cost of renewing the
pipes, due to rapid wear, made the retention of the
hydraulic stowing process questionable when the
Deutscher Kaiser Colliery, at the instigation of one of
its directors (Mr. Mommertz) introduced at shaft No.
11/V the wrought iron pipe with porcelain lining. After
numerous failures, but eventual success, the'porcelain-
lined piping was taken into permanent use. This
piping is manufactured by the Gewerkschaft Deutscher
Kaiser at their rolling mills in lengths of 4 to 5 metres,
with inside diameters of 125, 145, 165, and 185 milli-
metres. About 71,400 metres of this pipe are in use up
to the present, 31,780 of which are installed in this com-
pany. The price per metre of piping 145 millimetres in
diameter (which is the size most generally used) is 24
marks for 5 metre and 25 marks for 4 metre lengths
f.o.b. Rotterdam, the weight being about 45 kilos per
metre. The porcelain used is of the very best, with a
degree of hardness of eight, and it can therefore stand
the roughest material. The inside diameter of the
wrought iron mantling pipe is somewhat larger than the
outside diameter of the porcelain-lined pipe, the inter-
vening space being filled with cement. Before deciding,
however, in favour of the adoption of the porcelain-lined
pipe, the characteristics of the material to be stowed
must be fully known. Coarse-grained material should
not be used with this class of pipe, and must be reduced
to 30 to 40 millimetres cube.

The opinions of experts vary concerning the useful-
ness of the porcelain-lined pipe. At one place this pipe
stands very well, but at other places it is not so sue-