654

THE COLLIERY GUARDIAN.

March 26, 1915.

CURRENT SCIENCE AND TECHNOLOGY.

The Coal Resources of South Rhodesia.

In Geological Survey Bulletin No. 4, the director, Mr.
H. B. Maufe, states that Mr. Lightfoot lias completed a
survey of the Wankie coalfield, and has proved the
succession of beds and the conformability of the
escarpment grits to the coal-bearing series, as claimed
by Mr. Molyneux. The structure of the coal banns is
simple, and is due chiefly to a system of step-faulting.
Fossil plants have been discovered, and the determina-
tion of Glossopteris, &c.,by Dr. Newell Arber, establishes
the age of the beds as that of the Karroo system.
There are large resources of coal in the Wankie coal-
field, and there are also beds of valuable fireclay. In
the same bulletin, Mr. A. R. Thomson, general manager
of the Wankie Colliery, describes the method of v\ orbing
the coal. There are three workable seams, of which the
lowest is now being mined. The seam is 16 ft. thick at
one end, thinning to 4 ft. at the other, 16 miles away.
It is reached by an incline shaft, 600 ft. long, dipping
1 in 7. Where this shaft reaches the seam, it is con-
tinued as a main drift, and two slants are likewise
driven at angles of 45 degs. to the main drift. From
these, at intervals of 300 ft. in the main drift and 425 it.
in the slants, levels are driven at light angles to the
main drift, In developing the main dip heading three
separate headings are cut, leaving 100 ft. pillars between
them. The centre heading serves as the haulage road,
the side headings being used as return airways. All the
levels are driven in pairs intake airway and return),
with a pillar 50 ft. wide between them. In working the
coal it has been found that coal-cutting machinery, for
various reasons, is not so satisfactory as the Elliott
hand-boring machine with twist drills, which suits
native labour. In the first operation 5 ft. 6 in. of coal
are extracted from the seams averaging 8 ft. 6in. in
total thickness. The top coal lorms a useful reserve,
easily got under a pressure of orders. Ordinary main
rope haulage is used to the foot of the shaft, actuated
by a compound steam engine, but in the main roads an
electric haulage gear is in operation. Preparation for
the market is performed by three shaking screens with
tipplers, shoots, elevators, picking tables, and side
refuse conveyors. The washery is capable of dealing
with 20 tons per hour, and is driven by a 50-horse power
motor. The finer sizes are treated in felspar jigs, but
the larger sizes are separated without felspar. Two

Tectonic axes.	Ireland and Great Britain.	Fran e and Belgium.	Holland and Aix-la-Chapelle.	Rhenish- Westphalia.
Syncline of Dinant	Carboniferous beds south of Barnstaple	Basins of Taisnieres andAulnoye. Basin of Condroz	Basin of Eschweiler	Basin of Witten.
Anticline of Con- droz	Mendip axis, N. Downs	Hills of Artois. Con- droz ridge	Saddle of Aix - la - Chapelle	Saddle of Stockum.
Syncline of Namur	Coalfields of Ireland, Pembroke, S. Wales, Bristol and Kent	Basin of the Boulon- nais. The great Franco - Belgian coalfield	Extreme south-west of Limbourg. Basin of Worin	Basin of Bochum.
Anticlinal of Bra- bant	Cambro silurian massif of Wales, Lancashire basin and coalfields of central England. Pennine chain	Massif of Brabant	Saddle of Kerkrade. Central part of Lim- bourg	Saddle of W a 11 e r- scheid. Basin of Essen. Saddle o f Gelsenkirchen.
Syncline of the Campine	Yorkshire c >alfield and its extension	Contral part of the Campine. North of the Campine	North part of Lim1 ourg. Horst of Erkelenz- Bruggen. Horst of the Peel	Emscherbasin. Saddle of Gladbeck. Lippe basin.

analyses of the coal are given. -Finally, Mr. Maufe
gives an account of the resources of' the coalfield, which
he places at 419,317,000 tons actual reserve, and
550,094,000 tons probable reserve. The output in 1912
was 216,140 tons, and the total value of the coal sold to
that date was £603,227.

The Propagation of Flame in Gases.

In the Transactions of the Chemical Society, 1914,
vol. 105, there is a contribution by Dr. R. V. Wheeler
describing the results of experiments made in order to
examine the conclusions arrived at in 1883 by Mallard
and Le Chatelier. These authors found that when a
gaseous mixture in a horizontal tube closed at one end
is ignited at the open end the flame travels for a short
distance at a uniform speed, which is followed by a
“vibratory movement” of irregular character, occa-
sionally causing the flame to be extinguished. Mallard
and Le Chatelier studied the influence on the speed and
duration of the uniform movement of the diameter,
length and material of the tubes. Dr. Wheeler confirms
the results of the earlier researches. As a_ rule, the
diameter of the tube necessary to avoid cooling by the
walls and the consequent retardation of the flame must
be greater the slower the speed of the flame. The
duration of the uniform movement for any mixture
increases with the diameter and length of the tube up
to a certain maximum, beyond which increase in length
makes no appreciable difference. As regards the
composition of the mixture, Mallard and Le Chatelier
found that the speed of the uniform movement increases
with the percentage of methane in the mixture up to a
certain maximum, after which it decreases regularly.
Also the maximum speed is obtained, not with that
mixture containing the quantity of methane required
for complete combustion—viz., 9’4 per cent., but with a
mixture containing about 12 per cent, of methane.
These latter results are not borne out by Dr. Wheeler’s
curves, which show practically no difference between the
speeds attained in mixtures containing from 9*45 to
10*55 per cent, of methane. Near the lower and higher

limits of inflammability, which for horizontal propaga-
tion are 5'4 and 14'3 per cent, respectively, the curve
flattens, becoming nearly horizontal, near the higher
limit. A diagram is given in which Dr. Wheeler
superimposes the curves obtained by himself and by
Mallard and Le Chatelier, in which these differences are
clearly seen. It is noticeable also that Dr. Wheeler’s
maximum velocity was obtained nearer the 9'4 mixture
than was found by Mallard and Le Chatelier. In another
series of experiments in a large spherical explosion
vessel Dr. Wheeler found that the maximum velocity
was obtained in a 9'5 per cent, mixture, after which it
remained practically constant up to 11 per cent, thus
agreeing closely with the results obtained in the horizontal
tube.

The Campine Coalfield.

In the Bulletin de la Societe de 1’Industrie Minerale,
F. Schmidt contributes a lengthy paper on the relation
of the Campine coal field to those of Western Europe.
The author traces the whole history of the researches
Lading up to the development of this coal field, the first
coal seam of which was reached by a boring in 1901.
Much of the geological history of this discovery traverses
ground more or less familiar from the early researches
of Marcel Bertrand. An exceptionally clear account is
given of tectonic features of this area. The Caledonian
movement having impressed its stamp on the Cambrian
and Silurian strata, the subsequently deposited Devonian
and Carboniferous beds were thrown into a series of
folds called Hercjnian by Bertrand, and Armorican by
Suess, which correspond also to the Variscan folding of
central and eastern part of Western Europe. The
course of these folds, consisting of a series of anticlinals
and synclinals, is shown on a map of Western Europe,
and upon the accuracy of this interpretation depends
much of the author’s conclusions. In his view, the
syncline of Dinant parses through Cornwall and curves
in a north-easterly direction to the south of Vervieis
and to Eschweiler, in Germany. The syncline of Namur
includes the South Wales coal field, the Kent coal field,
Pas-de-Calais to Bochum ; while the syncline of the
Campine is made a part of the Pennine flexure, and its
course would thus have a profound influence upon the
extent of the Yorkshire coal field in the concealed area.
The following tabular .view represents clearly this
reading of the tectonics of the Campine :—

The author quite fairly states the differences of opinion
regarding this view as held by A. Habets, M. Delmer,
M. Kiusch and M. Stainier, and it must be admitted
that the question is still open to considerable discussion.
The author then passes from the regions of speculation
to the facts connected with the discovery of the Campine
coalfield, tracing the early investigations of Andre
Dumont leading to the Asch boring, which reached the
coal on August 2, 1901. The Campine field is then
described in detail, and a tabular view is given of all the
borings in Belgium and Holland in the Campine area,
with the thickness of strata penetrated and coal seams
found in each case. The question of the limits of the
coal field is also discussed, and an exhaustive account
is given of the coal beds and the nature of the barren
measures. The paper concludes with a bibliography of
the . subject treated, and the whole forms one of the
most comprehensive compilations that has yet been
published on this new coal field.

The Effects of Smoke in Colliery Disasters.

“ Smoke a Factor Complicating Carbonic Oxide
Poisoning in Colliery Disasters ” is the title of a short
contribution to the British Medical Journal (March 20,
1915), by Dr. E. Emrys-Roberts, professor of pathology
and bacteriology in the University of Wales. He
observes that many divergencies in the symptoms of
CO poisoning have been obseived from time to time,
and that these have rightly been attributed to the
admixture of other gases. But the part played by
smoke, produced at the time of the explosion, or fire,
does not appear to have met with the consideration its
importance deserves. In addition to CO and CO2,
smoke contains numerous irritant gases, compris’ng
sulphurous and nitrous fumes, acetic acid and ammonia.
These dangerous and irritant gases when met with,
especially as a result of underground fires, in dense
volumes in a confined space, give rise to immediate
symptoms of a profuse running at the eyes, and
coughing, accompanied by a sensation of poisoning.
These immediate symptoms may give place to those of

CO poisoning, if the latter gas has been inhaled, and may
thus become virtually masked in the more evident
state of CO poisoning. The irritant gases present
in smoke, hov\ever, when inhaled under such circum-
stances, produce after a certain lapse of time, generally
a few hours, a well-marked remote effect upon the
lungs. In the moie fortunate cases bronchitis is
superadded to the symptoms of CO poisoning, but in
severe cases acute oedema of the lungs, or even broncho-
pneumonia, may develop. The develoj ment of th* se
complications may naturally increase the dangers of
.CO poisoning very considerably, and cases are on
record in which the greatest difficulty has been
encounteied from this cause.

Since the irritant gases present in smoke are fieely
so'uble in water, it might be advantageous to emphasise
the value during exposure of tying a wet cloth ovtr the
nmuth and inhaling through it, and at the same time to
point out the fallacy of employing a dry cloth for the
same purpose.

TRADE AND THE WAR.

Coal Prices Enquiry Concluded—The Dye Scheme : A Poor
Subscription List—Speeding Up Production : Board of
Trade Memorandum — Lord Kitchener's Threat to
Shirkers — L.G.C. Coal Supplies — Government and
Surplus Profits—Dearer Gas in London—Norway Short
of Coal.

The committee appointed to enquire into the causes of
and possible remedies for the high price of coal are now
understood to have completed their investigation, and are
preparing their report. The committee have found, we
believe, that the main causes of increased cost are those
which might have been anticipated—diminished supply due
to shortage of labaur, increased factory and naval consump-
tion, and cold weather. The cost of freightage, however, is
regarded as an important factor, and the committee make
suggestions for the better organisation and speeding up of
traffic. The theory put forward by many agitators that
there has been deliberate exploitation is not accepted.

The applications for shares in the British Dyes Limited
have been poor. Only 880 applications for 571,000
shares were received, and of this number 83,000 were
conditionally applied for. Having regard to the serious
results to many industries if the scheme should fall through,
the directors took the exceptional course of calling
the subscribers together to give the latter full opportunity
of considering the position, with a view to the subscriptions
being increased. The meeting was held on Wednesday. It
was then stated that an additional £200,000 would be
required to launch the scheme, and this would be secured
by an increase of 50 per cent, in the subscriptions. Many
firms immediately promised to make such an increase, aud-
it was decided to proceed with the scheme. Several large
users of dyes have declined to subscribe.

Before the Birmingham and Midland section of the
Society of Chemical Industry on the 4th inst., Prof. Percy
Frankland lectured on “ The Chemical Industries of
Germany.” For the manufacture of dyestuffs and similar
synthetic products, he said Germany was formerly largely
dependent on England for the raw material—coal-tar. But
in recent years Germany had made strenuous efforts to
recover the maximum amount of coal-tar both from the
manufacture of gas and from coke ovens, which endeavour
had been promoted by the enormous growth in her iron and
steel industries. Thus in 1897 Germany obtained only
52,000 tons of coal-tar from coke ovens, while in 1908 she
obtained no fewer than 632,400 tons from that source,
besides 300,000 tons from the manufacture of gas. Thus at
the present time the German output of coal-tar about
equalled, if it did not exceed, that of England. The pro-
posal of the Government to assist the British coal-tar colour
industry was being watched with the greatest interest both
by manufacturers and chemists. The problem of relieving
the immediate shortage during the war must be carefully
distinguished from the later problem of securing the inde-
pendence of the home industry after the war by greatly
increasing the British output. The industry would require
“ nursing ” for many years. Chemists must form an integral
part of the directorate, which must be prepared to spend
large sums of money on judiciously conceived and well
organised research, for which the sum of £100,000 in ten
years, hitherto mentioned by the Government, was ridicu-
lously inadequate.

The Government proposals for establishing a national
dye industry were reviewed at the annual meeting of the
Institute of Chemistry, held on the 1st inst., by Prof.
Raphael Meldola, the retiring president, who emphasised
the point that the problem was primarily a chemical and
not a business one. About 500 different dyestuffs of definite
composition had been provided as the products of chemical
research. Of these a certain number only could be made in
this country. The Government scheme provided for new
and enlarged factories, but unless something more were
done there would still be after the war an outstanding
number of other products which had never yet been made
here, and for the working out of these processes no combina-
tion of “business” talent was of the slightest value. It
was by chemical research alone that our colour industry
could be saved. The Government promise of a grant for
10 years of “ not more than £100,000 for experimental and
laboratory work ” was a welcome concession, but who was to
direct that research ? The experts were to be subordinated,
and their assistance was to be invoked at the discretion of
a board, the members of which could have no real knowledge
of the conditions necessary for producing the materials
they required. The “ staple products ” upon which they
were asked to stake their capital might a few years hence
be superseded by the products of subsequent discovery.

The Board of Trade have issued a memorandum of
proposals for accelerating the output of munitions of war,
to which the workmen’s representatives of the conference on
the subject at the Treasury last week have agreed to
recommend to their members. It is proposed that there
shall be no stoppages of work on munitions and equipments
of war during the period of the war, and that subject to any
existing agreement or methods now prevailing for the
settlement of disputes, differences of a local character shall
be the subject of a deputation to the firm, and differences
of a general character shall be the subject of conferences