June 16, 1916.

THE COLLIERY GUARDIAN.

1143

J. W. BAIRD AND COMPANY,
'pitwood importers,
WEST HARTLEPOOL,

YEARLY CONTRACTS ENTERED INTO WITH COLLIERIES.

OSBECK & COMPANY LIMITED,

PIT-TIMBER MERCHANTS,

NEWOASTLE-ON-TYNE.

SUPPLY ALL KINDS OF COLLIERY TIMBER.

Telegrams—“ Osbecks, Newcastle-on-Tyne.”

*** For other Miscellaneous Advertisements see Last
White Page.

AND

Journal of ths Coal and Iron Trades.

Joint Editors—

J. V. ELSDEN, D.Sc. (Lond.), F.G.S.
HUBERT GREENWELL, F.S.S., Assoc.M.I.M.E.

(At present on Active Service').

LONDON, FRIDAY, JUNE 16, 1916.

The London coal trade still sutlers from short
supplies. House coals by rail are coming forward
with greater regularity, but seaborne supplies are
scarce, and no free coal is offering. Hard steam
and small nuts are in strong demand.

The Tyne and Wear coal trade is hampered by a
shortage of tonnage, and prices have weakened in
consequence. Coke is cheaper. In addition to
holiday irregularities, the stronger demand for house
coal in consequence of colder weather made matters
worse in Lancashire, Yorkshire and the Midlands.
Prices in South Wales have declined under the
influence of Government restrictions and tonnage
shortage. The market in Scotland is not uniform,
for the west reports an improved tone, combined
with uncertainty regarding foreign trade, whereas in
the east supplies are obtainable second-hand at a
few shillings below colliery quotations.

Lady Markham sold 30,000 tons of house and
manufacturing coal by auction in the London Coal
Exchange, on Wednesday. Keen competition pre-
vailed, and the sale yielded £11,000 for the Wounded
Allies Belief Eund.

Vessels chartered for coal cargoes to the Piraeus
are still held up in British ports, although the
Government has modified the embargo on Greek
vessels loading for neutral ports generally.

The Advisory Council for Scientific and Industrial
Research has formed a Standing Committee on
Mining, to represent both the scientific and industrial
sides. Sir William Garforth has been appointed
chairman.

Lord Strathclyde, neutral chairman of the Scottish
Coal Trade Conciliation Board, has awarded the
Scottish miners (90,000) an advance of 12| per cent.,
or 6d. per day.

Freights, like coal prices, have been irregular this
week. A dearth of tonnage is reported.

Several important papers were discussed at a
meeting of the Mining Institute of Scotland. A
report of the proceedings appears in this issue.

The Miners’ Federation will hold a meeting in
London, on June 29, to consider the attitude of the
miners on questions to be discussed at a special
Trade Union Congress at the Memorial Hall on the
following day. These include the regulation of food
and fuel prices, and the increase of old-age pensions.

The first pithead baths in South Wales were
opened on Thursday, at the Treharris Colliery of the
Ocean Coal Company Limited, by Miss Davies, of
Llandinam. The charge for using the baths will be
6d. a week.

London borough councils, after conferring together,
are considering proposals for economising coal
consumption by the joint working of electricity
undertakings.

The members of the Manchester Geological and
Mining Society will visit Llay Main Colliery, near
Wrexham, on Monday next. At a meeting on
Tuesday, Mr. F. Schmidt will read a paper on
a Shaft-sinking by the Freezing Method.”

A memorandum has been issued by the Board of
Education with the object of furnishing suggestions
to teachers and organisers of schools which provide
part-time courses in coal mining. There is nothing
obligatory in the proposed methods of teaching or
organisation.

The paper read by Mr. T. F.
Pyrites and Winmill on “The Atmospheric
Gob Fires * Oxidation of Iron Pyrites ” seems to
resuscitate a view’ which had been all
but discarded, as to the influence of pyrites in the
production of gob fires. From the results of an
interesting series of experiments he has been led to the
conclusion that where finely divided pyrites occurs in
considerable proportion among coal, it may be the
chief factor in originating combustion. As a support
to this contention, he shows that it affords an intelli-
gible explanation of the fact that in North Stafford-
shire small heaps of coal left at the face have been
known to fire in from 24 to 48 hours, a phenomenon
which could hardly be ascribed to the oxidation of
the coal itself. At the same time, he is careful to
explain that this result can only be expected to
follow when the proportion of pyrites is considerable,
since even 30 per cent, of this mineral in an
extremely finely divided state would only produce a
thermal effect equal to that of a normal oxidisable
coal. That is to say, such a mixture of pyrites and
coal would heat about twice as fast as coal alone.
It is only the finely disseminated pyrites that pro-
duces this effect, and brassy lumps and veins con-
tribute nothing to the initial heating.

These conclusions seem to be quite legitimately
drawn from the experiments, if we accept the implied
assumption that any sample of pyrites ground to a
degree of fineness represented by a 200-mesh sieve
behaves in the same manner on oxidation. That is
to say, Mr. Winmill ignores any difference in the
rate of oxidation and heat production between
rhombic pyrites, or marcasite, and cubical pyrites,
or mundic, provided that both are reduced to the
same degree of fineness. The disseminated pyrites
in coal is generally believed to be in the form of
marcasite while the visible “ brass ” is usually in the
form of mundic. Since Mr. Winmill appears to
have performed his experiments with finely ground
mundic, the quantitative heat effects he obtained
cannot properly be assumed to apply also to marcasite
without overthrowing one of the established doctrines
of the mineralogists respecting the relative stability
of allotropic forms.

We say that it is an established belief that marca-
site possesses a higher potential energy than mundic,
but this is probably overstating the case, because we
do not know that any conclusive experiments have
been performed with the object of showing that the
heat of oxidation of one form is different from that
of the other. It has been assumed that the potential
energy of marcasite is greater than that of mundic,
but the only proof is to be found in the instability
of the former and the stability of the latter under
ordinary atmospheric conditions. The usually accepted
explanation is based upon physical theories of
crystalline symmetry, into which we cannot now
enter. But Mr. Winmill has presented the matter
in a somewhat different light. He appears to assume
that this question of crystalline stability is one of
surface alone—i.e., that the greater resistance to
oxidation of the cubical pyrites as compared to that
of rhombic pyrites resides on the outside faces of the
crystals alone, and that if both are broken up they
will be equally susceptible.

This assumption seems to strike at the very root of
the modern theory of crystalline structure, and it can
scarcely be accepted without more . direct proof than
the paper affords. Mineralogists are accustomed to
view every portion of a crystal as being absolutely
identical in physical properties with the whole.
That is to say, the smallest part of any crystal has
the same symmetry, heat energy, and other properties
as the whole crystal. It is, of course, possible that
by grinding mundic it is transformed into marcasite ;
for the heat developed by grinding might conceivably
produce this result, since marcasite has the lower
specific gravity and greater specific volume. But
against this view we have the experiments of Allen,
Johnston and Crenshaw pointing- in the opposite
direction, since they found that at 450 degs. Cent,
marcasite is transformed into pyrites, a result which
is hardly consistent with the fundamental principle
of van ’t Hoff, and others, of the connection between
heat and chemical transformation. If, however, it is
assumed that mundic is transformed into marcasite

by grinding, Mr. Winmill’s conclusions would at
once be consistent with thermo-chemical principles.
Or, as an alternative, it may be suggested that
crushing may produce the amorphous state of
Sir G. T. Beilby.

As a matter of fact we know very little about
marcasite beyond the fact that it oxidises with
remarkable facility. There is good reason to
conclude that the chemical constitution of iron pyrites
is not so simple as to be correctly expressed by the
formula FeS2. Recent researches lead to the
conclusion that it is rather to be regarded as a solid
saturated solution of sulphur in the monosulphide
FeS. But we know little about the degree of
polymerisation exhibited by the mineral, ‘or its
molecular condition or indeed anything definite about
its composition.

The |thought naturally arises whether such theo-
retical considerations have any practical significance
whatever. We seem here to be somewhere on the
borderland between physical chemistry and practical
mining, but we hope Mr. Winmill will not leave
the matter in its present state. Many, both of a
theoretical and practical turn of mind, would like to
be assured that the rate of heat production of the
powdered cubical pyrites of the Ballachulish slates,
which endures for ages in its crystalline form, is, as
Mr. Winmill seems to imply, the same as that of the
marcasite which prevents the Sheppey fossil fruits from
being kept even for a few weeks as museum specimens*
After all, it is the rate of heat production that matters
most in the case of gob fires, and not the total heat
evolved.

Amongst the many remarkable situa*
Coal tions brought about by the great war
and now in progress throughout Europe
Shipping. none has attracted more forcible
attention than the vital importance
of British coal as an essential factor in the industrial
and military activities of the allied and neutral
Powers. The difficulties that have thus arisen have
called for drastic remedies hitherto unheard of in
modern history. Nor is this situation a mere
temporary phase to be at once alleviated by a return
to peace conditions. Even after the war a return to
normal conditions can only be expected to take place
gradually, and we are probably committed, for some
time to come, to a scarcity of tonnage, with the neces-
sary accompaniment of high freights and restricted
supplies, both in foreign ports and in British coaling
stations. In this connection it is highly interesting
to note the. persistent rumours that are afloat of a
projected combination of certain large colliery pro-
prietors and ship owners with a view to the conditions
that may be expected to arise after the war.

Amongst the factors which have undoubtedly
aggravated the present situation an important place
must be given to the methods available in home and
foreign ports for the loading and discharge of cargoes.
Every delay brought about by the want of adequate
port equipment means loss of earning power to the
vessels concerned and increased cost of fuel to the
consumer. Much has been heard of congestion of
tonnage from this cause, and although great improve-
ments in loading and discharging facilities are being
effected, there still remains a great deal to be done
in this direction.

Under these circumstances, we have thought it
advisable to examine in some detail the nature of
existing port equipments both at home and abroad,
and we have arranged for a series of illustrated
articles by Mr. F. J. Warden-Stevens dealing with
this and allied subjects in a comprehensive way, in
which it is proposed not only to discuss coal supplies
available for export and bunkering throughout the
world, but also the facilities for loading and
discharging at shipping ports- and coaling
stations. In addition to this, it is intended to
deal generally with the question of the economics of
steamship bunkering. Mr. Warden-Stevens is
already known in the coal shipping world as the
author of numerous articles touching upon this
question, both in the columns of the Colliery Guardian
and elsewhere. It is a branch of the coal industry
which has scarcely received the treatment, to which
it is entitled by its paramount importance even in