628

____________________________________________________________________________________________________________

THE COLLIERY GUARDIAN

September 24, 1915.

Division.

Scotland	.......

Northern .....

Yorks and North

Midland _____

Lancashire,North

Wales, & Ireland

South Wales ...

Midland and

Southern....

Total 1914 ...

Total 1913 ...

Table A.—Electricity in Use at Mines in 1914.

£

c6

£

340

279

240

137

291

131

1,470

2

Pi

c3

<D

Pl

s'§

Aggregate horse-power of electricity in use.											Total underground and on surface.
On the surface.						Underground.					
Winding.	Ventila- tion.	Haulage.	Coal washing and screening.	Miscel- laneous.	Total.	Haulage.	Pumping.	Portable machinery.	Miscel- laneous.	Total.	
2,991	5,6511	3,478i	7,281	10,7811	30,1831	30,134f	50,9321	22,1491	3,755T%	106,9724	137,155f%
11,118	18,6441	10,0631	13,485f	25,6241	78,9361	40,681	42,6571	4,245f	3,2911	90,8751	169,81If
1,4621	10,2921%	3,0541	21,5374-8	29,510t%	65,857-1-8	28,699	16,366f	9,124	3,600f	57,790-1	123,648^8
268	3,2921	1,0311	3,1801	5,345|	13,1171	10,5451	9 8891	832	1,235	22,502-1	35,620
16,3721	17,924	14,6931	9,5281	35,314 !	93,832-1	42,783	55.0951	7991	1,7611	100,4431	194,276
2911	2,2161	1,5341	3,3571	4,7641	12,1641	18,3331	19,012	2,428	L332t%	41,105|	53,2701%
32,5031  34,0451	58,02.11% 47,096	33,856  31,428	58,3711 52,181|	lll,340o%  91,925| •	294,092r%  256,6751	171,1761  151,9274	193,9531  171,5761	39,5781  35,704	14,980| 12,213-1	419,689f6  371,4211	713,782|  628,097f

Table B.—Number of Machines, Motive Power Employed, and Quantjty of Mineral Obtained by their
Use in the Various Inspection Divisions in 1914.

Division.	Mines using machines.	No. of machines.	I	Mineral obtained by machines.				Percentage of total output.		L Of eyors  J face.	
			Elec- tricity.  Tons.	Com- pressed air.  Tons, i	Total.  Tons.	Total 1913.  Tons.			!  £ f  <  <	1	COIJ V  1 at coa
	19141913						1914	1913	1914	1913
Scotland 		—* 228	913	! 7,865,480	1,330,165 ■	9,195,645	9,335,452	21’0	19’7	128	125
Northern 		92 89	702	1,256,433	2,317,879 |	3,574,312	3,545,249	6’4	5’4	68	58
Yorks, and North Midland		—* 164	725	3,556,410	3,57%729;	7,133,139	7,608,530	10’5	10’3	116	86
Lancashire, North Wales and Ireland 		95 107	399	355,650	1,733,922 i	2,089,572	2,167,951	7’9	7’6	27	27
South Wales			58 41	131	242,742	392,079	634,821	639,719	IT	IT	63	61
Midland and Southern 		60 48	223	931,846	715,181. i	1,647,027	1,313,057 i	5’6	4'4	6	2
Total in 1914		— —	3,093	14,208,561	10,065,955 !	24,274,516	_ !	8'7	—	408	—
Total in 1913		— 677	2,897	14,310,312	10,299,646 ;	—	24,609,958 '	; —	7'9	—	377

* No particulars.

Table C.—Mechanical Coal-cutters Employed in the United Kingdom in 1914.

Kind of machine.	Scotland.	Northern.	Yorks, and N. Midland.	Lancashire, N. Wales, and Ireland.	South Wales. 		Midland and Southern. | 	 i	1  Total  1914.	1  Total  1913.
Driven by electricity:—  Disc 		515	58	157	7	3	35	I  775	725
Bar 		216	33	87	19	38	20	413	377
Chain 		12	63	104	8	3	29	219	193
Percussive 		2	2	—	.—	—	—	4	5
Rotary heading 		2	—	2	—	—	—	4	7
Total 		747	156	350	34	44	84	1,415	1,307
Driven by compressed air:— Disc 				119	61	175	117	1	i 14	487	518
Bar 	,		7	15	60	34	50	:	6	172	165
Chain 		—	8	35	5	7	!	20	75	57
Percussive 		40	451	99	209	29	■	94	922	836
Rotary heading 			—	11	6	—	— '	; 5	22	14
Total 		166	546	375	365	87	! 139	1,678	1,590
Total in 1914 		913	702	725	399	131	i 223	3,093	—
Total in 1913 		876	665	673	393	115	j 175	—	2,897

during these 12 months, and that this progress has
been observable in almost every direction. It is
distinctly a matter for congratulation that the death
of only four persons below ground, and the same
number on the surface, should have been traceable to
the use of electricity last year ; this is five less than
in 1913, and only one more than in 1912, when the
whole of the collieries were idle for some time.

Table A shows that the aggregate horse-power of
electric motors in use above and below ground in
1914 was 713,782^-horse power, as compared with
628,097j-horse power in 1913. The increase of
134 per cent, is rather less than in the previous year,
when it was 22-9 per cent. ; if we take into account,
however, the reduction of output, there is a very
significant increase in the tonnage of mineral gotten
per electrical horse-power employed. The develop-
ment has been common to all districts, and has been
equally distributed over the surface and under-
ground workings. More than half of the total
horse-power is employed in haulage and pumping,
and the first of these applications may be expected to
extend very rapidly in the years to come, as mining
engineers become convinced of the advantages of

secondary mechanical haulage in the rapid clearance
of the output from the faces

Tables B and C relate to the use of coal-cutting
machines. It will be seen that there is an increase
of nearly 200 in the number of machines employed,
and that a greater proportion of the reduced output
was wrought by machinery. The increase has been
rather more marked in the case of electrical machines
than in the case of those driven by compressed air,
and it may be noted that there has actually been a
reduction in the number of compressed air disc
machines, the main increase being that of percussive
machines, a type that has rather different functions
to perform from the other types of machine, and does
not readily yield to electrical treatment. But those
who consider that the days of compressed air are
numbered should read the informative paper that
has just been read before the Institution of Mining
Engineers by Mr. Sam Mayor. Circumstances, such
as the explosion at the Wharncliffe Silkstone Colliery,
may even favour the replacement of electricity by
compressed air for work at or near the face.

One of the most remarkable developments during
the year has been the increased use of portable

electric safety lamps The figures may be summarised
as follows:—

Number of Plame Safety
Lamps.

Type.	1914.	1913.

Daw ______ 1,049... 10,202
Clanny .... 193,521. .301,570
Mueseler ... 72,044... 35,473
Marsaut ... 395,139 337,553
Wolf ...... 17,593... 11,934
Other sorts. 226... 43,269

Total.... 679,572...740,001

Number of Electric Safety
Lamps.

Type. 1914. 1913.

Gray-Sussmann 8,556... 10,283

Ceag ........ 41,866...24,237
Oldham...... 14,643... 2.420

Wolf ......... 6,895... 503

Joel-Fors ... 491 )
Other sorts ... 256 i

Total..... 75,707...37,823

The number of electric lamps has thus been doubled

in a year, and it is noteworthy that in 1912 only

10,727 electric safety lamps were in use. It is
obvious that the flame safety lamp has in many cases
been superseded by the electric lamp, but, without
entering the vortex of a somewhat heated controversy,
we may say there are no real signs that the oil lamp
has fallen upon evil days. The decline in the number
of flame lamps is largely to be accounted for by the
banishment from the mine of a considerable riumber

of lamps that did not comply with the new official
test, and the probability is that within a few years
most of the flame safety lamps in use at British
mines will belong to one of two main types—the
Marsaut and the Mueseler.

The following statistics are added with regard to
the use of explosives in 1914 :—

1914.	1913.

Explosives used (lb.)........... 25,521,098 ... 26,335,195
Tons of mineral raised per lb. of

explosive used...............	10’9	...	11’7

Estimated number of shots fired:

By electricity .............. 22,834,030 ... 23,179,841
By fuse .................... 13,193,488 ... 14,608,725
By squibs........................... 9,762,128	... 11,045,720

Total __............ 46,089,646 .. 48,834,286

Tons of mineral raised per shot

fired . ....................	6'0	...	6’2

Number of missed shots.......	38,983 ...	41,410

There is a remarkable variation in practice in
regard to the use of explosives. The quantity of
mineral obtained per pound of explosive used varies
from 40’8 tons in the Yorks and North Midland
Division, and 22'5 tons in the South Wales Division,
to 6’4 tons in the Northern Division, and 6T in the
Scotland Division. In Scotland 80 per cent, of the
shots were fired by fuse, and in the Northern Division
over 50 per cent, by squibs.

Apart from the normal development of mechanical
methods, there was, of course, a lot of work carried
out last year in connection with devices entailed by
the provisions of the Coal Mines Act. Notable
instances are the use of overwind and speed controllers,
reversible fans, and electric and mechanical signalling
apparatus. Unfortunately there is no accurate
means of determining the number of such appliances
that have been installed at collieries during the
year. The first and last have afforded great scope
for individual predilections and have given rise to
much confusion in the minds of those called upon to
use them. The extensive structural alterations that
have been carried out on underground roads, shaft
bottoms, &c., have also made their demands upon
the mechanical engineer, who has become a very
much more important personage at the colliery than
he was a few years ago.

The conviction is steadily growing, indeed, that in
the times of unwonted stress that lie ahead a great
and almost exorbitant call must be made upon
machinery in the working of mines. The financial
and other serious problems concerned demand the
concerted action of mining engineers, if it be impos-
sible to persuade the State that it has a responsibility
in securing the future development of the industry on
safe and economic lines, other than its whilom duties
as a policeman.

________________________________

Partnerships Dissolved.—The London Gazette announces
the dissolution of the following partnerships :—R. Livisey
and D. J. Gould, coal and coke merchants, at the Great
Western Railway Y’ard, Merthyr Tydfil, under the style of
Livisey and Gould; H. Rix, W. Moore, W. Stoddart, and
J. D. Paton, foundry specialists, at Stretford-road, Man-
chester, under the style of Rix, Moore, Stoddart and Com-
pany; H. E. How, C. L. Arnold, and C. R. Belling,
specialists in electric heating, at Derby-road, Edmonton,
Middlesex, under the style of Belling and Company; W.
Lancefield and C. Lancefield, haulage contractors, general
carriers, and coal and coke merchants, at Sellindge, near
Hythe, Kent, under the style of Lancefield Brothers: J.
Burgess and R. Burgess, engineers and shipsmiths, at Cleve-
land-street, Birkenhead, Chester, under the style of J. and
R. Burgess.