April 20, 1917.

THE COLLIERY GUARDIAN.

763

for safety as well as for the purpose of guide props
for the cutter (fig. 10).

(13) Surface Props.-—The official in charge of the
timber yard should be regularly consulted by the
underground timber official, so as to gauge the use of
the quantity in stock, etc. ; and where collieries have
their own timber cutting appliances, the underground
official should advise the surface official of the pro-
bable requirements, in order to prevent the cutting of
excessive amounts of one size and not sufficient of the
others, etc.

Conclusion.—These are, then, the practical and
practicable points which the author has gathered in
connection with the economical use of timber in the
course of his experiences down the mines. There
must be, unknown to him, many other means by which
timber can be saved. The object of this paper is,
therefore, to invite discussion in the hope of securing
a valuable selection of workable suggestions, > with a
view to their adoption in all collieries, in order to
utilise the available timber resources of the country
to their greatest advantage and in the national
interests.

COAL OUTPUT AND MAN POWER.

The Coal Controller has submitted to the workmen’s
organisation in the coal trade a new scheme for taking
further men from the mining industry for the Army.
The War Office and its military advisers must be tl e
unquestioned authority as to what the military require-
ments for men will be in the coming month.

What the coal-producing industry asks—and this
applies to every industry in the country—is that the
requirements of the Army should be met with the
minimum amount of dislocation of an essential industry.
This is as important to the State as it is to the
industry.

The new scheme of the Coal Controller seems
admirably designed to secure the maximum of results
with a minimum of disturbance to the trade.

Take.the manner in which the men are to be drawn
from the various collieries. It is proposed to do this by
bringing the enlistment quota of each colliery up to the
average of the district in which the colliery is situate.
If this principle is properly observed in the enlistment
of further men, each colliery will supply up to a fixed
average percentage of the men employed. It is common
knowledge that there has been the widest possible
divergence between the ratio of enlistments at different
collieries even in the same district. Certain collieries
have been denuded of an unduly high percentage of
their workmen, from the eagerness with which the men
joined the Army. Other collieries have suffered a
relatively small loss of men. The position was put
with admirable clearness by Sir Thds. Ratcliffe-Ellis to
the Coal Organisation Committee: “ I have cases
particularly in my mind,” said Sir Thomas, “ where such
a large number of men have gone from the collieries
that they have not a sufficient amount of labour under-
ground, and they cannot get it, to enable the roads to
be kept in repair and the haulage to be worked by the
persons ordinarily occupied in that work, and the collier
has to be withdrawn from his proper work of getting
coal to do that which would be done by other persons if
labour was available.” To take further men from
collieries in such a plight as that would do mischief of
a serious kind to the economic position of the industry,
and also of the country. If the Coal Controller under
this scheme can equalise the position as between one
colliery and another, he will have succeeded not only in
making the burden of sacrifice equal, but will achieve
the more important result of economic fairness to the
coal trade.

Then the scheme is also fair and just to the workmen.
It is proposed to take first the single men in the lower
age group from 18 to 23 or 25, and proceed thence, if
necessary, to recruit single men from the higher age
groups and the married men from the lower age groups.
This is a method which will cause the minimum of
hardship and disturbance with the maximum of results,
so far as the Army is concerned. The first need of the
Army is young men. This is a young man’s war. It
has been proved conclusively that the taking of men at
the higher ages is a mistake, from the large percentage
of breakdowns under training. It is economically an
unsound policy for the military authorities to take men
who give a large percentage of failures in training. It
fills the hospitals with invalids at a moment when the
demand for beds for the treatment of the wounded are
clamant and difficult to meet, and it deprives the nation
of the producing power of these men in the industries
from which they have been drawn. Therefore the pro-
posals of the Coal Controller, acting doubtless with
the concurrence of the Advisory Committee, are sound
in principle, and should prove effective in practical
operation.

Coal for Spain.—It is stated that, as a result of the visit
of Marquis Cortina to this country, the British Govern-
ment has agreed to supply Spain with 150,000 tons of
coal monthly. In return, Spain will export to England as
much ore as required. The Spanish Government agrees.to
allow the chartering of Spanish ships by the British
Government.

Coke Production in Queensland.— The Queensland
Minister of Mines (Mr. Hamilton), in. company with
officers of his department, recently visited. New South
Wales to enquire into the position of coal mining and the
coke industry. He returned to Queensland impressed
with the possibilities before the Government’s mines, and
appeared to be fully determined to embark on the produc-
tion of coke with by-product ovens.

North of England Institute of Mining and Mechanical Engineers.

In the absence of the president (Mr. Frank Coulson),
Prof. Henry Louis occupied the chair at the meeting
of members of the North of England Institute of
Mining and Mechanical Engineers, held on Saturday
afternoon last in the lecture theatre of the Wood
Memorial Hall, Westgate-road, Newcastle-on-Tyne.

New Members.

The following gentlemen were admitted into the
institute: —

Members.—Mr. L. Allison, mining engineer, T’ung
Hsing Sino Foreign Coal Mining Company Limited, Men-
t’qu-Kou, vid Peking, North China; Mr. A. H. Askew,
mine manager, Boulby Grange, Loftus, Yorkshire; Mr.
M. B. Bell, colliery manager, Orchard House, Capheaton,
Newcastle-upon-Tyne; Mr. M. F. Cheesman, colliery
manager, Throckley Colliery, Newburn, Northumberland;
Mr. J. Cockburn, colliery manager, Trimdon Grange
Colliery, co. Durham; Mr. T. Ford, colliery manager,
Blaydon Burn Colliery, Blaydon-upon-Tyne; Mr. F. W.
Jenkins, mining and chemical engineer, 1, Burgess Parade
Mansions, Finchley-road, Hampstead, London, N.W. ; Mr.
A. A. D. Jones, mining engineer, India (at present on
active service); Mr. J. Longridge, colliery manager, The
Bungalow, Ginteen, Castlecomer, co. Kilkenny ; Mr. C. A.
Pattison, colliery manager, Evenwood, Bishop Auckland ;
Mr. P. Ryle, colliery manager, South View, Crook, co.
Durham; Mr. T. E. Slater, colliery manager, Ystrad-
gynlais, Breconshire; Mr. C. Southern, mining engineer,
Radstock, Bath; and Mr. W. Watson, mining engineer,
Settlingstones Mines, Fourstones, • Northumberland.

Associate Members.—Mr. F. J. Roden, Clarence House,
Chesham; Mr. H. S. K. Simpson, P.O. Box 56, Dundee,
Natal, South Africa; and Mr. F. T. Walker, 27, Wood-
bine-avenue, Gosforth, Newcastle-upon-Tyne.

Associate.—Mr. G. Nattrass, colliery under-manager,
Redheugh Colliery, Gateshead-on-Tyne.

Subscribers.—The Bearpark Coal and. Coke Company
Limited, Royal Exchange, Middlesbrough; the F ramwell -
gate Coal and Coke Company Limited, Milburn House,
Newcastle; the Moresby Coal Company Limited, near
Whitehaven; the Seaton Burn Coal Company Limited,
Akenside House, Newcastle; and the Workington Iron
and Steel Company Limited, Moss Bay, Workington.

Power Production and Utilisation.

Mr. Mark Halliday continued the discussion on Mr.
F. F. Mairet’s paper on “ The Economical Production
and Utilisation of Power at Collieries.”* He stated
that, in reading the paper and the contributions to
the discussion, he had been surprised to find such a
variety of opinions regarding the cheapest method of
producing energy. It appeared to him that the reason
for that was the absence of an agreed unit or units as
a basis of comparison. Although the figures on costs
of generating power on the basis of the output of the
mine, and also on the basis of the kilow’att hour or
horse-power hour, were extremely useful and neces-
sary, each one in itself was insufficient to indicate the
working conditions of the power plant. It occurred
to him that, if the number of kilowatt hours per ton
of mineral raised, and also the cost per ton raised,
were ascertained in each case, a valuable standard of
comparison would be obtained, and the cost of produc-
ing power per kilowatt hour could be derived. Another
figure which it was desirable to obtain was the cost of
power per kilowatt year on the maximum demand over
any half-hour, which, in conjunction with the previous
figure, would give an indication of the load factor, the
importance of which could not be over-estimated. The
reason for that combination of figures- was obvious,
when one considered the variety of conditions prevail-
ing at collieries. He was aware that serious objec-
tions might be raised to registering power on these
lines. It was an easy matter to obtain full consump-
tions and labour costs, but units of power could not
be so readily measured. At a colliery worked exclu-
sively by electrical energy obtained from a supply
company, the power consumption was easily recorded
on an integrating kilowatt hour meter, and, therefore,
presented no difficulties. To obtain the result at a
steam-driven colliery presented a rather more difficult
problem, and one which required a fairly considerable
amount of time and skilled labour. It could, how-
ever, be arrived at fairly accurately by the use of the
continuous indicator for winding and hauling engines
and ordinary indicator diagrams for engines on steady
loads. A complete record of the work done during a
wind or by an engine bringing out a set could be indi-
cated on the continuous diagram, and the results
rapidly calculated by measuring the areas of the
diagram with a planimeter. The whole of the work
done could be recorded thus over a given period, and a
fairly average set of conditions obtained which would
serve as a useful basis for comparison. On any power
plant he would advocate the adoption of recording
apparatus wherever possible if the engineer was to get
the best results. All feed water should be measured
by such instruments as the Lea recorder, which would
give a check on the evaporative capacity of the
boilers. Most of the progress already made was due
to the adoption of measuring instruments which invari-
ably exposed defects and waste. Further, in allo-
cating the costs of utilising power, he would say that,
for the sake of comparison of such costs as winding,
it would be better to calculate on the basis of a ton
raised per 1,000 ft., and not simply on the depth of
the mine where the tests might happen to be carried
out. A convenient basis for haulage costs was the
ton-mile. With regard to the production of energy,
undoubtedly the central electrical power station linked
up with waste heat stations was by far the most econo-
mical means of production. One might also safely
say of its utilisation that a colliery operated solely by
electrical power would consume less units per ton of

* Colliery Guardian, July 21, 1916, p. 114.

coal than by any other method. As to whether it was
cheaper for the colliery owners, depended upon the
terms of supply. One fact in favour of central
stations was that of national economy. One recent
type of steam engine had not been referred to in the
paper, viz., the uniflow or “ central exhaust ” engine.
Where suitable terms could not be obtained from a
power supply company, he would say that, for a
colliery requiring power up to about 1,000 horse-power,
the uniflow engine stood unrivalled for economical
steam consumption and capital costs. For compara-
tively small units, it had the advantage over the tur-
bine of being as economical at full load and more
economical at lower loads. With steam superheated
to 600 degs. Fahr., and at an initial pressure of 150 lb.
per sq. in. at the stop valve, almost constant steam
consumption of 10 to 11 lb. per indicated horse-power
per hour had been obtained for loads varying between
50 and 100 per cent, of full load. At a recent test on
one of these engines at a colliery with which the
speaker was connected, the results for a period of 8|
hours’ test carried out by the British Boiler and Elec-
trical Insurance Company for Messrs. Cole, Marchent
and Morley Limited, the engine builders, indicated a
consumption of 14*49 lb. on boiler feed per indicated
horse-power per hour with steam at 61*7 lb. per sq. in.,
and a total temperature of 401 degs. Fahr., and a
vacuum of 27*3 in., with the barometer at 29*8 in.
The steam conditions were not favourable for the test.
The average load was 440 indicated horse-power. The
steam was supplied from a Lancashire boiler, 30 ft.
long by 8 ft. diameter, and, in order to prevent steam
from blowing off during the test, the furnace doors
had to remain open for a considerable time, thus
admitting cold air, which reduced the temperature of
the gases, and hence the steam leaving the super-
heaters, below that obtained under normal conditions
when other engines were also drawing steam from the
boiler. If this figure were corrected for temperature,
it would be found that the consumption, with steam
at 575 degs. Fahr, (which was the average working
condition), was 12*34 lb. per indicated horse-power—
a figure comparing favourably with turbines of power
below 1,000 horse-power working under similar steam
conditions.

Col. W.C. Blackett remarked that they were bound
to agree with Mr. Halliday.

The discussion on Mr. Mairet’s paper then closed.

Notes on Safety Lamps,

The discussion of Mr. Simon Tate’s paper,
“ Further Notes on Safety Lamps,”* was resumed.

Prof. F. W. Hardwick (London) wrote stating that
the paper written by Prof. O’Shea and himself was
intended to arouse interest in the subject, and to evoke
from members information either supplementing,
amplifying, or correcting that given by the authors.
If that result were attained, one would then possess a
complete and accurate record of the invention and
development of a contrivance which undoubtedly had
conduced to the safe working of collieries, and had
contributed largely to the growth of Great Britain’s
industries and commerce. The writer was inclined to
think that Mr. John Buddle’s improvements in venti-
lation commenced before 1815, for, in his letter of
1813 to the Society in Sunderland for Preventing Acci-
dents in Coal Mines, Mr. Buddle described an impor-
tant method of his for circulating the air currents;
whilst Mr. R. L. Galloway had mentioned an improved
effect by Mr. Buddle at Wallsend G pit in 1810 by
dividing the air current. In his evidence before the
Select Committee on Accidents in Mines, 1835, Mr.
Buddle appeared to indicate the year 1807 as that in
which he commenced his new system, and he stated:
11 It was some time before I got it fully into practice,
because it was not in accordance with the views of
many of the old and experienced pitmen.” Prof.
Hardwick went on to draw attention to the following
extract from a letter written by Mr. J. Murray to the
Mining Journal in 1844 :—“ In an old (folio or quarto)
work—the Acts of the Leyden Savants or of Leipsic—
the precise title of which I do not now remember, will
he found a lantern of gauze referred to as a safety
from ignition by gunpowder; also an article on the
application of the bellows to blow air under or through
water into a lantern. ... I only recollect that, on
reading them (the facts) at the time, they forcibly
struck me as being remarkable, in reference to Sir
H. Davy’s wire gauze and Dr. Clanny’s bellows lamp
—but 28 years have rolled away since. I was assured
that the work in question was put into the hands of
Davy in 1816 in one of the libraries of Newcastle-on-
Tyne.” The writer had endeavoured to trace the
reference given by Mr. Murray, but, so far, without
success.

Mr. J. R. R. Wilson (H.M. inspector of mines)
said he noticed that Mr. Tate drew attention to the
fact that inspectors, when they visited the pits,
detected gas in working places which they could not
discover -in the report books. It was unfortunate that
that was a fact. He hoped they would also take it
for granted that the inspectors were experts at the
work of detecting gas. They were trained to the
work, and deputies ought to be the same. He fre-
quently got reports that, “ About 1| per cent., nearly
2 per cent., and so on, of gas was found in the canch,”
and, if samples happened to be taken at the same
time, it was remarkable how exact these estimates
were. The “ about 1| per cent.” might be 1*4, the
“ nearly 2 per cent.” about 1*8, and so on. They could
quite understand how, when he got thesv. estimates and

* Colliery Guardian, February 16, 1917, p. 332.