December 4, 1914.

TfiE COLLIERY GUARDIAN.

1183

be fitted with some absorbent, and used for the estima-
tion of both methane and carbon dioxide. The readings
would doubtless be of considerable value to the colliery
manager.

The writer constructed his present instrument about
12 months ago, and it has been repeatedly used in
several pits in Yorkshire and in the Midlands. The
advantages which he claims for it are as follows :—

(1)	Its absolute safety, owing to its purely mechanical
construction, without the use of electricity, a spark, a
hot wire, and, above all, a flame.

(2)	Its sensitiveness at low percentages, which greatly
exceeds that of the method adopted now for gas
detection.

(3)	Its mechanical strength and simplicity, there
being only two moving parts and nothing likely to get
out of order.

(4)	Its portability, as it can be carried in a pouch
slung to a belt round the waist of the deputy, its weight
being only 21b., and its size 6# in. long by 2i in.
in diameter.

(5)	The readings being direct and automatic, the
human intervention is confined to careful observation.
This the writer considers is the most important of its
advantages.

The writer has tested the instrument in several col-
lieries in the Leeds district, and its readings have been
compared with the estimations of gas made by skilled
officials, and with laboratory analyses of samples taken
from the same place. In most cases the correspondence
between the indications on the instrument and the other
tests has been very striking.

THE SUPPLY OF PITWOOD.

Railway Rates on British Timber.

Mr. Marshall Stevens, of Trafford Hall, Manchester,
sends us copies of lengthy correspondence that has
passed between him and the President of the Board of
Trade with reference to the railway rates on British-
grown pit timber. In his first letter, dated Sept. 20,
Mr. Stevens suggested to Mr. Runciman that during
the closing of the Baltic there was an ample supply—
amounting to some millions of tons — of timber for
mining purposes in this country, which only required
an equitable adjustment in the railway rates of carriage
to bring it into use. It was suggested that it was only
necessary for the Board of Trade to insist upon a
schedule of rates for British timber compiled for dis-
tances of more than 100 miles upon the basis of the rates
in operation for foreign timber for similar distances
from West Hartlepool, for any difficulty of supply of
colliery timber to disappear. It is provided that the
rates should be applicable to all descriptions of round
timber; rates must be available for measurement, as
well as for machine weight; and rates need not be
applicable to 2-ton or 4-ton loads, but may be limited
to full wagon loads, for even if the railway company
provide 30- or 50-ton wagons, there will be no difficulty
in giving full loads for them.

In replying to this and further letters, the President
of the Board of Trade intimated on November 3 last
that he understood that the railway companies were
prepared to quote under certain conditions modified
rates for the conveyance to collieries of pitwood in
lengths not exceeding 14 ft., and a number of such rates
had been quoted. Applications for rates should be
made in the ordinary course to the railway companies.

Following this came a letter from the secretary of the
Railway Executive Committee, stating that the com-
mittee were prepared to put the following exceptional
rates into operation. Such rates were quoted subject
to the conditions shown, and, when not inconsistent
therewith, to the conditions contained in the general
railway classification, and also in the rate books of the
various companies over whose railways the traffic would
pass. The rates would not be entered in the railway
companies’ rate books, and the committee reserved the
right to alter or withdraw any of these rates or condi-
tions without notice. In any case, the rates would not
apply after the termination of the war.

Between	Kind of traffic.	Excep- tional rate per ton.	
		s.	d.
Egloskerry and	o £		
Black Bull	<D <X> rfS  <D &D	19	3
Etruria		19	0
Harecastle	*	19	3
Bradley Fold	, not isign ffiint	20	9
Leigh and Bedford		20	5
Wigan	g § g	20	4
Adlington (Cheshire)	§ ® a	20	1
Okehampton and Black Bull	® d * Ils	18	0
Etruria		17	9
Harecastle	.5 'eg	17	11
Bradley Fold	d	19	5
Leigh and Bedford		19	1
Wigan		19	1
Adlington (Cheshire) _	S.S3	18	9

Condi-
tions.

The following memorandum was attached : “ This
quotation being for the purpose of enabling firms to keep
their works going, and not with the view of the convey-
ance of traffic at remunerative rates, is given on this
distinct understanding that it is not to be made use of
in any case in the future as an argument for rates of a
similar character, or upon a similar basis.”

On November 19 Mr. Marshall Stevens again
addressed the President of the Board of Trade, acknow-
ledging that the rates quoted formed a fairly good basis
for the arrangement he was wishful to bring about,
without, however, going sufficiently far to make them
of themselves useful. He thought the executive com-
mittee had not sufficiently considered the fact that

different colliery districts have different requirements.
These are all covered by a general quotation being given
for “ Deals, Battens and Boards,” from which varia-
tions are made in the Railway Clearing House classifi-
cation book, pp. 200 to 203, to cover varying require-
ments. For example, it is usual, having formulated
a rate for deals, battens and boards, for the companies
to carry short lengths of pitwood by actual weight at
10 per cent, under the deals, battens and boards rate,
the longer lengths being carried at measurement weight
and charged 20 per cent, over in consequence. Mr.
Stevens added that he had a considerable number of
trees felled in North Devon, approximating nearly. 1,000
tons, 75 per cent, of which would meet the best require-
ments of the Lancashire and North Staffordshire col-
lieries if forwarded in lengths averaging 20 ft. or more.
The same collieries would take the shorter lengths—the
tops of .the trees. He could not to advantage send the
25 per cent, of short lengths by rail and the 75 per cent,
of lengths longer than the 14 ft. (for which no quotation
had been offered) by water, because the smaller lengths
would* make such good broken storage in loading the
coasting vessel with the larger timber. It was neces-
sary, therefore, as already pointed out, that rates must
be given for measurement as well as for weight, and
that the destinations must not be limited to collieries,
although in this particular case the great bulk of the
timber would go to collieries.

To this the Board of Trade replied on November 27,
stating that it had not previously been represented to
them that there was any urgent demand for pitwood
exceeding 14 ft. in length. Any application for special
rates on deals, battens and boards that might be made
to the railway company would no doubt be carefully con-
sidered, but such rates would hardly appear to be
applicable to round timber. It was added that the
Board of Agriculture and Fisheries were about to issue
a leaflet stating that exceptional rates could be obtained.
Beyond this the Board did not think that they could
usefully ask the railway companies to publish a mileage
scale of rates for pitwood.

In his last letter Mr. Stevens reiterates that the rates
quoted by the executive committee—although reasonable
in amount for the small portion of the timber for which
they are quoted—would not enable him to send either
the pitwood or the other timber cut with it throughout
by rail.

INDUSTRIAL LOCOMOTIVES.

Views of Mining Engineers.

There was much of interest to colliery owners, managers,
and engineers in the discussion at the meeting of the North-
East Coast Institution of Engineers and Shipbuilders at
Newcastle on Friday of last week, on Mr. J. W. Hobson’s
paper on “ Industrial Locomotives,” which was published
in the Colliery Guardian on November 13 and 20.

Mr. C. N. G-oodall, managing director of Messrs. Robert
Stephenson and Company Limited, averred that if a loco-
motive was not good enough for railway work, it was not
good enough for industrial purposes, where it would be sub-
jected to very much harder and more strenuous work. He
discussed the difficulties arising from tube-plate erosion,
and said he found that in America the trouble was practi-
cally unknown there. This was due, he found, to the
peculiar formation of the tube-plate—shaped like a drum
head, with flange turned towards the front. The formation
of that plate left very little room at the bottom for the
accumulation of ashes, and, consequently, when washing out
was done, there was nothing to absorb the wet and set up
corrosion. He emphasised the necessity for proper use of
the ashpan.

Mr. F. Bowman, engineer to Messrs. Chas. Perkins and
Partners’ collieries at Birtley, described in detail the loco-
motive, “ Charles Perkins,” which Mr. Hobson had men-
tioned in his paper. He stated that the engine was working
very satisfactorily at the coal shipping staiths of the Birtley
Iron Company, and ran over a railway on which was rope
haulage, having the necessary rollers, etc., and certain low
bridges which had to be negotiated, thus necessitating a
design of locomotive somewhat unique. Its leading par-
ticulars were: Cylinders, 14 in. diameter by 22 in. stroke;
four wheels coupled, 3 ft. 6 in. diameter, with a wheel base
of 5 ft. 6 in. suitable for curves of small radius; heating
surface, 590 sq. ft.; grate area, 8*87 sq. ft.; working
pressure, 1501b. per sq. in.; water capacity, 580 galls.; fuel
capacity, 30 cu. ft.; weight of engine in running order, 27
tons; maximum height, 8 ft. 4| in.; maximum width, 8 ft.;
gauge, 4 ft. 8J in.; length over buffers’ beam, 19 ft. 5| in.;
no part of the wheels to project below 7J in. from top of
rail; and buffers designed to suit the company’s box wagons.
He gave it as his experience that, where brass tubes were
used, corrosion occurred around the tube holes, due to gal-
vanic action. To obviate such corrosion of the steel tube-
plate, his firm had used for some years steel tubes with
copper ends to take the copper firebox plate.. The difference
in expansion was overcome by the copper being placed inter-
nally in the steel tube. As to preventing the pitting of the
boiler shell, their practice, which gave good results, was to
give the barrel a coat of bitumastic solution. In view of
the experience which they had had with one of their 16 in.
six-wheeled locomotives, when considering the makers’
specification for the “ Charles Perkins,” the question of
copper or Yorkshire iron rivets for the firebox was discussed.
The makers contended that iron rivets held the plates
together more efficiently. He still maintained, however,
that conditions of work and the character of the feed water
should be considered, and no general practice and selection
of material carried out. His firm executed its own loco-
motive repairs to some 18 engines in all, and its practice
was to put copper rivets in copper boxes. In the case of
the wasted iron rivets, there was no doubt that the feed
water used was of a saline character. Most coast waters
contained considerable quantities of sodium chloride, which
concentrated in a boiler with the formation of salt scale.
The rivets constituted a crude thermopile, and, in many
cases, probably acted as electrodes. Copper was acted or,
very slowly by acids, except in the case of nitric acid. He
concluded, therefore, that a mixture of metals in a locomotive
boiler was not always desirable, and that a steel boiler
shell with steel tubes and steel firebox might be necessary
in some conditions of working.

Sir Benjamin Browne, chairman of Messrs. Hawthorn,
Leslie and Company, locomotive builders, wrote that many
engines did not give satisfaction because they were not the
right engines for the job. An engine in a coke yard or
factory might be simply perfect for shunting, collecting,
and distributing wagons, and such like, and yet quite
incapable of a long, steady pull. It had never had to go a
quarter of a mile without stopping, and, if someone put it
on a colliery line, where it might have to draw heavy trains,
possibly on unfavourable gradients, for a long distance, it
might fail completely. Therefore, it was desirable that a
customer should know something about the engine he
required, and that manufacturers should take more pains
to find out the best engine for any given work. His own
impression was that, although he did not believe that steel
would generally supersede copper, there were occasional
cases where steel might be safely used, when, of course, it
would be a great saving. As to whether locomotive
engines were likely to hold their ground as a permanent
institution, he remarked that stationary plant could only
be used economically where one had a large traffic. He
thought the tendency would be more and more to use electric
plant in towns and on all very crowded railways, but that
locomotive engines would still be used for the longer runs,
where trains were less frequent, and, above all, for new
railways. For these latter purposes he thought steam would
hold its own against anything else for a long time.

Mr. S. Tulip, engineer for the Lambton Collieries Limited
at North Biddick, said Mr. Hobson was wise in pointing out
how desirable it was, when selecting a locomotive, to have
it with a good margin of power. It was the worst possible
economy to work a locomotive up to the limit of its capacity.
There were certain kinds of machinery which would stand a
great deal of abuse, but a locomotive was not one of them.
It was worth while to go to some trouble and expense to
provide suitable feed water. The practice of treating the
feed water after it had passed into the boiler appeared to
have’ little justification. It was much better to make the
water suitable for boiler feeding by scientific treatment.
The use of saturated lime water and barium carbonate was
very suitable for softening the water which came from
the magnesian limestone of that district. Its cost might
be from Id. to l|d. per 1,000 galls., according to the price
of barium. Perhaps no part of a locomotive caused the
engineer so much anxiety as the firebox; yet its life might
be very much lengthened by careful nursing. In his
experience, the life of a copper firebox of a locomotive work-
ing 16 hours a day and fed with good water, might be from
10 to 14 years. As to the matter of costs, it was exceed-
ingly difficult to get reliable figures for engines of the class
under discussion. A company which owned 40 such engines
had, however, carefully kept a record of the cost over a long
period. The engines had to be maintained to the satisfaction
of the engineers of the main line railway over which they
ran. The practice was to wash the boilers out regularly
every eight days, and, at the same time, to make a careful
external examination and to do the slight running repairs.
Every two years or so the engines were thoroughly over-
hauled. The cost of upkeep, taken over a period of 20
years, was : Material, £88 0s. 5d. per engine per annum;
and labour, £77 16s. lOd.—a total of .£165 17s. 3d.

Mr. R. F. Spence, agent of the Backworth Coal Company,
wrote remarking that the local colliery mentioned by Mr.
Hobson as using steel fireboxes was, he had no doubt, Back-
worth, where there were 14 locomotives with cylinders from
15 to 17 in. in diameter. The boiler pressure was 140 lb.
per sq. in., the load 260 tons, and the gradient up to 1 in 60.
The average working hours were 80 per week. They fitted
their first steel box in 1884. It lasted 11| years, and was
scrapped—not through any fault of the box, which would
have gone another year. They had superseded copper
boxes gradually since then. They attributed their success
entirely to the care used in never blowing a boiler down hot
or washing out till cold. The only difficulty they had had
on tube cleaning days had been with an old box, when they
found that the ferrules were easily knocked out. The tubes
were of steel.

Mr. Hobson, in the course of his reply on the discussion,
said that a large amount of sulphur in coal was most
injurious to the engine, especially when the sulphur fumes
came in direct contact with the firebox plates or stay heads,
whatever material they were made of; and railway com-
panies’ specifications for the supply of locomotive coal gener-
ally stipulated its freedom from sulphur. A most important
factor was the adequate supply of air in the firebox. If that
was sufficient, any sulphur in the coal should not affect the
copper. If insufficient, however, there was a possibility of
the sulphur combining with the oxygen in the small amount
of oxide of copper always present in copper plates, and
affecting them deleteriously. He spoke favourably of the
idea of feeding the water into a tray suspended in the steanj
space, with a view to alleviating tube and stay troubles ana
incrustation. He was of opinion that the method was good
if properly handled hand and the tray kept clean. As to
large smokeboxes, the larger the smokebox the longer (in
practice) would the fireman let it go before cleaning out. He
laid stress on the importance of the reliability of the work-
ing parts of an industrial engine by pointing out that main
line engines were never called upon to control trucks down
grades of 1 in 13, where, if the brake gear failed, a serious
mishap would result; nor did they travel on railways where
the end of one rail was a couple of inches below the end
of the next one. Mr. *Hobson maintained that, in addition
to the care and attention given to the boilers at Backworth
Colliery, the feed water and fuel must be exceedingly
favourable, as other coal and iron companies had not had
similar experiences. Mr. Tulip had stated that cast iron
boxes in cast iron guides would work well together for a
number of years, but few colliery companies had the advan-
tage of having their own iron foundries, and it was a
common occurrence for the speaker's firm (Messrs. Haw-
thorn, Leslie and Company) to replace, at the owner’s
express wish, such boxes and guides with steel castings.

Mr. C. E. Ford, last Friday, gave an interesting paper to
the members of the Junior Institution of Engineers on the
subject of “ A Model Drawing Office System.” The author
only dealt with the system as applicable to electrical
apparatus, but said it could be applied to any branch of
engineering where a large amount of repetition work is in
operation with equal efficiency. On December 14, at 8 p.m.,
at the Institution of Electrical Engineers, Victoria
Embankment, a presidential address will be delivered by
the Most Honourable the Marquis of Graham, D.L., C.V.O..
C.B., on “ The War and Engineering.”