390

THE COLLIERY GUARDIAN

February 22, 1918.

INDIAN AND COLONIAL NOTES.

Africa.

Transvaal Coal Mining.—As the Transvaal colliery com-
panies have declared their dividends for 1917, it is pos-
sible to make a comparison with the dividends of the
previous year. It has been frequently pointed out that
the Transvaal coal mining industry as an investment suffers
from comparison with the Rand gold mining industry, and
its importance is therefore to some extent overlooked. Its
record is one of which investors need not be ashamed, and
every year—thanks to the Transvaal Coal Owners’ Associ-
ation—its position as an investment is gradually improving.
The Transvaal coal trade has probably received less direct
benefit from the prevailing war conditions than the coal
trade of any other part of the world. There are complaints
that the Coal Owners’ Association has been too modest to
take advantage of war conditions to the same extent, for
instance, as the Natal collieries ; but it is nevertheless a
fact that, whilst with only three exceptions, all the asso-
ciated collieries have declared a dividend, not a single non-
associated limited liability concern succeeded in distri-
buting a dividend last year amongst the shareholders.
Coming to individual collieries, the Apex, for instance,
paid a 12^ per cent, dividend to its shareholders last year,
compared with 10 per cent, for the previous year. The
Cassel Company also increased its dividend from 6| to 7|
per cent. ; whilst its neighbour, the Clydesdale Collieries,
now that they have taken to working Middelburg coal,
have also increased their dividend from 2^ to 5 per cent.
The Coronation, since it became closely associated with
the Victoria Falls Power Company, was able to pay a
dividend of 20 per cent. ; whilst the Middelburg Steam
Coal and Coke Company have paid the same dividend as
that for the previous year. That flourishing concern, the
Transvaal and Delagoa Bay Collieries, by working an addi-
tional colliery, have increased their dividend from 17^ to
22| per cent.; and both Tweefontein and Witbank
Collieries again paid 25 per cent, to their ordinary share-
holders. Even Welgedacht has increased its dividend
from 2^ to 3| per cent, on its gold and iron capital of
<£156,750, and although paying the smallest dividend of
any of the associated collieries, its record, under the cir-
cumstances, may be regarded as satisfactory. All the
above collieries are members of the Coal Owners’ Associa-
tion, and must have expended at least .£1,000,000 in work-
ing capital alone, whilst the dividends paid on that amount
silghtly exceed, on the average, 10 per cent., not an extra-
vagant profit, when everything is taken into considera-
tion. If we come to compare the non-associated colliery
results with those known to have been obtained at the
associated collieries, they cannot be deemed satisfactory.
Breyten Collieries show a very insignificant profit; whilst
it is reported that the Goldfields, tired of the coal trade,
are about to dispose of their controlling interest to Mitchell
Cotts and Company, the well-known coal shippers at
Durban and Cape Town. The Uitkyk Collieries, owing
to the inferior quality of the output, are again under a
cloud, and seem as far distant as ever from earning satis-
factory profits. There are several small privately-owned
non-associated concerns that promise to earn a profit, but
the majority of the non-associated collieries appear to be
suffering from a variety of drawbacks.

Australia.

Coal for Essential Industries.—The distribution of coal
to meet the needs of the essential industries has become one
of the pressing problems, in the Commonwealth, owing to
the shortage of shipping, which has been accentuated owing
to some of the vessels being made available for the Imperial
Government. It has been found necessary to utilise vessels
in carrying coal to,the more distant States, while Victoria
will be largely supplied by rail, but the extra expense
involved in haulage by rail will mean that the cost of coal
landed in Victoria will be higher than in West Australia,
South Australia, or Northern Queensland, where supplies
are sent by sea. It is proposed, therefore, that the States
confer on the question of pooling the charges, so that such
a State as Victoria will not be penalised.

Losses Through Strike.—One result of the recent disas-
trous strike in New South Wales has been that the
Australian Coal and Shale Employees’ Association, which
has a State membership of 19,000, all of whom were fully
four weeks out of work, have lost .£228,000 in wages alone.
Other unions have, been seriously affected, and the total
loss incurred by the men must be close on one million
pounds. Another result which is most satisfactory to the
general community is that a new and chastened spirit is
exhibited by the men. At Newcastle, a new union, known
as the Iron and Steel Industry Employees’ Union, has been
formed by the employees of the steel works. Its objects
are to protect and foster the interests of its members, to
promote and maintain industrial peace, to foster and
encourage harmonious relations between employer and
employee, and to settle matters in dispute by means of
arbitration. Provision is made for a conciliation com-
mittee, to which disputes must be referred. In the event
of any dispute arising, there is to be no cessation of work.
If these conditions be faithfully observed, it will indeed
be a pleasing change from the old truculent “ stand and
deliver ” methods of the militant unions, who for so long
have had sway in New South Wales.

Coal Production in Western Australia in 1914.—The
annual report (1916) of the Department of Mines, Western
Australia, states that the output for the year was 301,526
tons being 14,860 tons mone than in 1915. With the
exception of the Scottish Collieries Mine, where opera-
tions were suspended, the mines were actively worked.
The Collie Co-operative carried out a series of bores to
further prove the property, and the results were satis-
factory. The number of men employed, 458, is less by 40
than in 1915, and the output per man was in 1915, 575
tons, and in 1916, 658 tons.

In the Collie coal field the output of coal for the year
was 301,526 tons, and for the preceding year 286,666 tons ;
an increase of 14,860. The Co-operative Colliery Com-
pany carried out a series of bores for the purpose of
proving the property, and the results have justified the
expenditure incurred. A considerable amount of boring
with good results was also carried out on a prospecting
area, and sinking is now in progress. With the excep-
tion of the Scottish Collieries, where operations were sus-
pended on account of inflow of water, work was carried
on as usual at all the mines. The progress of the field
has been satisfactory.

Output. — According to the figures supplied by the
Under-Secretary for Mines of New South Wales, the aggre-
gate value of coal raised in the State is £196,000,000. The
production of coal for the year 1916 totalled 8,127,161 tons,

valued at £3,336,419. The quantity exported to Austra-
lasian and other ports during the first six months of 1917
amounted to 2,057,067 tons, valued at £1,480,450, as com-
pared with 1,861,899 tons, valued at £1,026,391, for the
similar period in 1916. The coal trade has been somewhat
dull, owing to the lack of shipping to supply foreign trade.
This, together with the great strike, which extended from
the first week in August to early in October, means a con-
siderable diminution of the output for the year. The pro-
duction of shale will show a decrease compared with the
previous year. The coke trade continued fairly brisk, most
of the product being used in Australia.

Canada.

Alberta Output.—The Mines Branch has issued a quar-
terly bulletin showing nine months’ output in the province
of Alberta. The quantity received at the ports of entry
in July, August, and September totalled 1,115,955 tons,
valued at 3,987,979 dols., and in the nine months January-
September, ■ 2,213,501 tons, a slight decrease on the corre-
sponding period in 1916. The output of lignite coal in
the nine months amounted to 1,592,046 short tons, com-
pared with 1,366,713 short tons in the corresponding period
of the previous year. The bituminous total was 3,172,725
tons, compared with 3,173,054 tons.

Mine Explosion.—An explosion at the Allan shaft of the
Acadia Coal Company’s collieries at Stellarton, Nova
Scotia, on January 23, caused the loss of 91 lives. Over
100 men were in the mine at the time of the explosion,
and some on the higher levels escaped, but all who were
on the lower workings, at a depth of 1,200 ft., lost their
lives. The cause is supposed to have been spontaneous
combustion, which caused previous disasters at this mine.

Fuel Shortage.—The problem of how to meet the serious
difficulty of fuel shortage due to war conditions is engag-
ing the attention of the Government and public bodies.
The Central portion of Canada is entirely dependent on
the United States for coal, and, owing to the extra demand
there for war purposes, and the shortage of labour, the
quantity available for shipment to Canada has been greatly
reduced. The situation has been aggravated by an
unusually severe winter and transportation difficulties. In
some places the municipal authorities have established fuel
depots to supply coal in small quantities to those in actual
need, and a strict supervision is exercised. Among the
remedies proposed is the utilisation of the extensive peat
resources of Ontario. Some years ago experiments were
carried on on an extensive scale by the Department of
Mines at Ottawa to ascertain whether the production of
peat fuel on a commercial scale to compete with imported
coal was feasible. A satisfactory fuel was produced, but,
with the price of American anthracite then prevailing, it
was found to be unmarketable. Since then, conditions
have greatly changed. Another proposal is the utilisation
of the lignites of Saskatchewan by carbonising and
briquetting, which, it is claimed, will produce a fuel at
7-25 dols. per ton, or considerably less than the cost of
imported anthracite in the leading cities of Manitoba and
Saskatchewan. The project is not a new one, having been
investigated and discussed some years ago by the Commis-
sion of Conservation; but in view of the present emer-
gency, and probable worse conditions in the future, is
likely to take practical shape.

TOLUOL FROM SOLVENT NAPHTHA.*

By Gustav Egloff.

To increase the supply of toluol without the delay
entailed by having to build scrubbers for the gas
plants, the author proposes the use of water-gas
machines to crack solvent naphtha, and produce
toluol in the presence of blue gas. That this is prac-
ticable is deduced from the following test conducted
upon a Lowe 6 ft. carburetted water-gas set, over a
period of 48 hours. The operation of the plant in
cracking solvent naphtha in the presence of blue gas
for toluol is practically the same as when cracking gas
oil in ordinary carburetted water-gas making, with
the exception that the gallonage per hour of solvent
naphtha into the cracking zone is higher. The data
upon a 24-hour basis averaged as follows for a car-

buretted water-gas set: —

Make per 6' set per day of gas formed .. 500,000 cu. ft.

Candle-power of the gas................. 21 at 21° C.

Candle-power of gas per gallon of oil .. 1*75 at 21° C.

Solvent naphtha cracked per 1,000 cu. ft.
of gas formed ........................ 12*0 gals.

Gas per gallon of solvent naphtha cracked 83*3 cu. ft.
Coke used per 1,000 cu. ft. gas ........ 46*0 lb.

Steam used per 1,000 cu. ft. gas ....... 38*0 lb.

Temperature of superheater base ........ 825° C.

Temperature of condenser outlet ........ 15*5° C.

Length of run........................... 4 min.

Length of blow ......................... 4 min.

Rate per hour solvent naphtha .......... 250 gals.

Rate actual flow of solvent naphtha into
system ............................... 500 gals.

Total gallonage of solvent naphtha passing
through set in 24-hour day ........... 6,000 gals.

Light oils collected in drips and seals. 57 ppr cent.

Tar in gasholder ....................... 15 per cent.

The light oil was distilled in a one-barrel still with
steam to a temperature of 170 degs. Cent. This cut
was analysed, and the analysis showed, on the basis of
light oil recovered from the cracking of solvent
naphtha, the following percentages of aromatic
hydrocarbons: —

Per cent.

Refined benzol................. 14*5

Refined toluol................ 23'7

Refined solvent naphtha...... 19*8

Crude heavy naphtha ..........  9’7

Dead oil....................... 14*0

On the basis of 100 gals, of solvent naphtha cracked,
the following percentage of aromatics can be
recovered : —

Per cent.

Refined benzol.................. 8*3

Refined toluol................ 13*6

Refined solvent	naphtha....... 11’2

Crude heavy naphtha ............ 5*5

Dead oil................;...... 0*8

In these critical times, with a high scarcity of
toluol, no quicker method lends itself to adding to the
toluol supply than the cracking of solvent naphtha in
carburetted water-gas machines, of which there is a
more than sufficient number already in operation,
which could be used at once without any change.

* Journal of Industrial and Engineering Chemistry.

NORTH OF ENGLAND INSTITUTE
OF MINING AND MECHANICAL
ENGINEERS.

The meeting at Newcastle on the 9th inst. discussed
Mr. F. L. Booth’s paper on “ The Strength of Pit
Props,” which was given on page 327 of our last issue.

Mr. C. C. Leach remarked that as to the strength of
the prop being the same irrespective of its length up
to about 4ft. bin., he dared say that would be shown
quite clearly in the tests Mr. Booth had applied to the
prop, but if, as in a pit, there was side pressure as
well as vertical, that would have a good deal of
influence on the prop.

Prof. Henry Louis congratulated Mr. Booth on
having got very fairly accurate figures, having regard
to the roughness of the methods employed. The
figures were almost identical with those the speaker
got in his paper of nearly 20 years ago. Mr. Booth
had measured the pressure applied to the inside of
the ram and not to the prop itself. The pressure
inside the ram was partly consumed in friction and
only the remainder was applied to the prop. That
was the reason, in the speaker’s opinion, that Mr.
Booth got a certain amount of exaggeration in his
smaller figures. The figure the speaker got for a large
number of imported Baltic props was 1-68 tons per
sq. in., in tests of a good many hundred props, all
of which were carefully squared and set in a testing
machine giving a dead pressure. In those tests 20
years ago, he found that very much depended upon the
seasoning of the timber. He found that thoroughly
seasoned props went up to just a little over two tons
per square inch, although made of the same wood as
the less seasoned props. In a report on pit timbers,
made by him for the Board of Trade in 1914, he got
for similarly thoroughly seasoned Norwegian timber,
1*29 tons per sq. in. Obviously, therefore, the ques-
tion of seasoning was one of exceeding importance and,
unless one had the exact condition of the seasoning
of the props, it was quite impossible to speak definitely
within two or three tenths of a ton per square inch.
The comparison between quartered props and round
props was quite interesting. He had tried to work it
out on the basis of formulse for pillars as admitted by
engineers, but had come to the conclusion that it was
impossible to apply formulae of that kind with any
satisfaction to such heterogeneous material as a pit
prop. They had, obviously, got a worse distribution
in the quartered prop than in the circular prop. In
the quartered prop, the strongest wood came at the
apex of the triangular piece, where it had the least
effect in resisting crushing action. On the whole, he
was a little inclined to think that Mr. Booth had hardly
got out quite as good a figure as he should have
expected for the quartered prop. He (the speaker)
should have put the decrease in strength at about
20 per cent., quite roughly. He found, with Mr.
Booth, in his early experience with Scottish fir, that
the green wood was very much weaker than ordinary
Norwegian props. The conclusions to which he came
in that earlier paper were practically the same as those
Mr. Booth had come to now. He quite agreed with
Mr Booth that the crushing of prop was independent
of its length, within reasonable limits. It was usually
admitted, in engineering text books, that, in order to
treat a strut as a pillar, the length should be not less
than four times the diameter. He thought that, when
they got that condition, the strength was independent
of the length. Most pitmen would tell them that a
long prop fell more rapidly than a shorter one, but
that was because the prop usually fell at some weak
part, a knot or something of that sort, and the longer
the proper the greater the chance of such a point
of weakness. He thought Mr. Booth’s work was a con-
tribution of distinct value to that very important
branch of the work of mining.

Dr. J. B. Atkinson remarked that when he was in
Scotland 20 years ago it was quite common in the Slam-
annan district, where a number of valuable steam coal
seams were being worked to make use of quartered props.

Mr. F. C. Lee (Ashington) remarked that the mining
industry of this country had never suffered from the
shortage of pit props to the present extent, and the
surplus of ohe class of timber gave little compensation
for the shortage of another, if the former were not
made economically and efficiently serviceable in place
of the latter. As regards the quartering of large-
sized props, everybody knew that small pieces of
timber cut from larger pieces could be used at a coal
face in place of the small round and whole props, but
everybody did not know the exact or even the approxi-
mate sizes of the former to be employed as substitutes
for the latter. The result was, in order to err on the
side of safety, the splitting and quartering of pieces
of timber that were far too large, whilst the pieces to
be used as substitutes were much in excess of the
strength they need have been. From the standpoint
of safety, that practice was, of course, quite admissible,
but from the standpoint of safety combined with
economy and of making the most of an available stock,
it ought not to be encouraged. The tables and con-
clusions come to by Mr. Booth formed clear guidance
as to the requisite sizes to be employed in place of
round and whole props of similar sizes. Another point
invaluable to mining engineers, managers, and
other officials at collieries was the statement that
certain sizes of quartered props as substitutes
for certain classes of whole props were entirely
in accord with safety. If a fall of roof should
take place in a district in which these supports
were used, the manager or other officials could, both
from a humanitarian point of view and as a guard
against the intervention of the Coal Mines Act, always
conscientiously state that such a fall could not have
been avoided or prevented even if the ordinary round
and whole props had been in use. Mr. Booth had
made it clear that no particular care was exercised in
the setting of the pieces during the tests; the figures
obtained were, therefore, all the more useful in prac-