1096

THE COLLIERY GUARDIAN.

May 31, 191g.

MINE MANAGERS’ EXAMINATIONS.

We have received from the Secretary of the Board
for Mining Examinations copies of the questions set
at the examinations for certificates of competency
as managers and under-managers of mines and for
certificates of qualification as surveyors of mines,
which were held by the Board on May 22 and 23 at
Edinburgh, Newcastle, Sheffield, Cardiff, Wigan and
Birmingham.

The text of the papers is given below. (Note.—The
figures in brackets against each question indicate the
maximum number of marks obtainable.)

For First-Class (Managers’) Certificate of Competency.

Subject No. 1.—Winning and Working.

(Six questions only to be answered. No. 3 is compulsory.)

1.	Describe the characteristics of millstone grit. To
what formation does it belong, and what is its relation-
ship to the coal measures? (40)

2.	A roadway is 10 ft. wide and 7 ft. high under the
bars. A fall occurs to a height of 20 ft. above the rails.
What precautions would you take before removing the
debris^. Describe in detail, with sketch, how you would
make the road again fit for traffic. (40)

3.	Compulsory Question. — What difficulties and
dangers have to be guarded against in very shallow mines ?
What are the difficulties connected with deep mining, and
how may they be minimised ? (50)

4.	In a horizontal seam worked longwall, what are the
determining factors regulating the lengths of the drawing
roads (gateways or stall roads), and from your expe-
rience, what are the maximum and minimum lengths that
have been adopted ? When these roads have reached the
length which is considered sufficient, how is the new cross
road made, and what is usually done with the old roads?
Illustrate your answer with a plan. (40)

5.	Make a rough drawing of a bricking scaffold for a
sinking pit, designed so that the scaffold ropes shall act
as a safe guide for the hoppit; Show by sketch how the
scaffold is held in position in the shaft when the hoppit
has to pass through it when sinking is progressing, and
the kind ‘ of rider you would use, so as to allow the
detaching hook to pass through the rider. (40)

6.	Sketch in plan and cross section an underground
stable suitable for 20 horses. Give approximate dimen-
sions. What arrangements would you make for feeding
and watering ? (40)

7.	It is decided to fix rigid guides in a shaft. Compare
the merits of wood guides and steel rails for this purpose.
Show by plan the position of the guides if either system
is adopted. How would the guides be jointed, and how
would they be secured to the bearers; also what distance
would you allow between the bearers ? (40)

Subject No. 2.—Theory and Practice of Ventilation.

(Six questions only to be answered. No. 6 is compulsory.)

1.	Indicate by means of the usual symbols how you
would ventilate the workings of a mine shown on the
accompanying plan (fig. 1) with six splits, including one-
required for the stables. (30)

2.	When the equivalent orifice of a mine is 16 sq. ft. and

Fig. 2.—Subject
No. 4. Machinery.

Qn. No. 2 (1st Cl.).

Fig. 1.—Subject No. 2. Ventilation.

(Plan referred to in Qn. No. 1 (1st Cl.) and Qn. No. 2 (2nd Cl.).

The open working faces requiring to be ventilated are distinguished by a thick black line ; the open
airways and haulage roads, by two parallel lines. All the rest of the space within the edge of the solid coal
is filled with stowing. There are to be six splits of air, including stables.

its water gauge 3 in., what quantity of air is passing
through the mine when a cubic foot of air weighs 0-075 lb. ?
(30)

3.	Sketch (on a scale of about one-half its natural
size) and describe the Clowes lamp in detail. What is
the principal difference between caps shown in this lamp
and those shown in an ordinary miner’s lamp when both
are burning in the same mixture of firedamp and air ?
Why do the caps differ from each other ? (30)

4.	What are the various causes of resistance to the
passage of air through a heading in a mine? State the
conditions under which that resistance is greatest and
least with the same velocity of air current and what should
be done to secure the least resistance possible. (30)

5.	A given fan engine, on being indicated, is found to
be developing 150 horse-power. The quantity of air
passing through the mine is 180,000 cu. ft. per minute and
the water gauge is 4 in. What percentage of the power
is absorbed in doing useful work? (30)

6.	Compulsory Question. — Sketch in detail an air
crossing both in plan and in sectional elevation, the latter
viewed from a point in the intake airway. The intake
airway is to be used as a haulage road and is to pass
under the return airway. The structure is to be composed
of brickwork, iron girders and timber. (50)

7.	What are the limits of inflammability of mixtures of
firedamp and air ? What are the products of their com-
bustion? What is the temperature at which ignition of
the mixture takes place? (30)

Subject No. 3.—Explosions in Mines, Underground Fires,
and Inundations.

(Five questions only to be answered. No. 3 is compulsory.)

1.	What are the principal causes of the production of
dangerous coal dust underground ? Where is it most
likely to be found, and what steps would you take to
prevent its production and deposit? (25)

2.	Discuss the question of watering coal dust in a deep
dry mine, and state your own conclusions. (25)

3.	Compulsory Question.—How would you proceed
with an investigation into the cause and the point of
origin of an explosion in a mine? (30)

4.	Set out a time-table showing the number of men
required for carrying on rescue work continuously over
24 hours in the neighbourhood of the pit bottom, the base
being at the surface. (25)

5.	Discuss the relative merits of longwall and pillar-
and-stall (or stoop-and-room) systems of working a seam
of coal liable to spontaneous combustion. (25)

6.	In working a seam of coal under the sea, what factors
would you take into consideration having regard to the
danger of flooding? (25)

Subject No. 4.—Machinery.

(Five questions only to be answered.)

1.	A direct acting pump is working against a head of
150 yds. The steam cylinder is 12 in. in diameter, and
the double acting ram is 6 in. in diameter. Stroke 24 in.
The rising main is 7 in. inside diameter. What should
be the pressure of steam for driving the pump ? Neglect
friction. (28)

2.	The accompanying drawing (fig. 2) shows by front
and side elevations a mild steel suspension link for a
shaking shoot. The two holes, which were originally
round and 1^ in. bore, are worn oval as indicated. How
would you propose to repair the link so as again to have
round holes to take 1^ in. pins? Illustrate your answer
by dimensioned sketches made in your answer book. (38)

3.	What is a mixed pressure steam turbine, and for
what purpose may it be used at a colliery ? Compare a
steam turbine and a high-speed enclosed vertical engine
for driving an electrical generator. (28)

4.	In connection with a new colliery being laid out on
a large scale and needing underground power for pumping
and hauling, describe the measures to be taken to
economise in the consumption of coal. (28)

5.	Describe the construction of a cage, to comply with
the Coal Mines Act and Regulations, having two decks
each to hold two trams (tubs or wagons). Name the
materials used, and illustrate your answer by simple
sketches. In particular describe the construction of one
of the main uprights or hangers. (28)

6.	Describe the operation of lowering a double wire
armoured heavy electric cable, say 2^ in. in diameter, down
a shaft 400 yds. deep. How would you join the various
lengths of the cable together, and how would you secure
the cable to the shaft side ? (28)

Subject No. 5.—Surveying, Levelling, and Drawing.*
(Five questions only to be answered. Question No. 1 is
compulsory.)

1.	Compulsory Question.—Plot the following short
underground survey, and find the bearing and length on

plan of the line joining A and B. Surveyor candidates
will also calculate the co-ordinates of the survey, and
the bearing and length of AB on plan, and the length of
a road joining these points. (For table of natural sines,
etc., see below.) From A N. 40 degs. E. 250 ft. level;

S.	45 E. 200 ft. level; S. 47 W. 300 ft. rising 30 degs.;
W. 240 ft. level to B.« Plotting to be on a scale of 1 in.
to 100 ft. (30)

2.	Plan No. 1 (fig. 3) shows the sites of a number
of bores put down to ascertain the strike of the strata
and the dip thereof, and therefrom the line of outcrop
of the seam. The level of the seam above Ordnance datum
is given at each bore. Assume the surface to be. level
and 290 ft. above datum, and that the rockhead lies at
a uniform depth of 30 ft. below the surface. Trace the
line of outcrop, and say what information as to the lie
of the strata you deduce from the boring. (30)

3—Enumerate the various maps published by the
Ordnance Survey Department by reference to the scales
thereof, stating them in inches per mile., and as a ratio
to unity. (&) Draw’ a square representing one acre on
each of the three larger scales so arranged that each
square has one angle in common, (c) State how the line
of true north is defined on any one of the series of
maps. (30)

4.	If the starting loose needle bearing of a fast needle
survey be half a degree in error, what will be the approxi-

* For Surveyor’s Certificate.

mate error in feet at the end of ten bearings aggregating
1,000 ft. in length? In what way is such an error more
serious than similar small deflections of the needle in a
loose needle survey? (25)

5.	What is the length of Gunter’s chain in feet? Why
was this length adopted and divided into 100 links ?
Discuss shortly the advantages and disadvantages in mine
surveying of a chain and steel band, or tape, re-
spectively. (25)

OBore No. 1.

ONo. 2.

Coal Seam 200 ft.

Seam 250 ft.

ONo. 3.

Seam 190 ft.

ONo. 4.

Seam 240 ft.

ONo. 5.

Seam 140 ft.

ONo 6.

Seam 180 ft.

O No. 7.

Seam 120 ft.

ONo. 8.

Seam 160 ft.

Fig. 3.—Subject No. 5. Surveying, etc. Plan
referred to in Question 2.

(In the original, the horizontal distances between the
boreholes are on a scale corresponding to 200 ft., and the
vertical distances to 4t 0 ft )

6.	What is meant by magnetic declination? What is
the amount and direction thereof in your own district at
the present time, and how would you check and allow for
variations thereof in mine surveying? (25)

7.	Explain the principle of a vernier, and describe with
a sketch its application to a mining compass. Make
the sketch to show a reading of N. 45 degs. 8' E. (25)

Table of Natural Sines, &c.

Degs.	Sin.	Tan.	Cotan.	Cos.	Degs.
40 ...	0-642	... 0-839 .	.. 1-192 ...	0’766	... 50
41 ...	0-656	... 0’869 .	.. 1’150 ...	0-755	... 49
42 ...	0-669	... 0-900 .	.. i-iio ...	0’743	... 48
43 ...	0-682	... 0’932 .	.. 1’072 ...	0731	... 47
44 ...	0695	... 0-966 .	.. 1-035 ...	0’719	... 46
45 ...	0-707	... i-ooo .	.. i-ooo ...	0-707	... 45
	Cos.	Cotan.	Tan.	Sin.	
Subject	No.	6.—General	Management and		Mining

Legislation.

(Five questions only to be answered. No. 1 is compulsory.)

1.	Compulsory Question.—Describe an efficient sys-
tem of registering each workman underground in each
shift. (30)

2.	What are the various restrictions concerning the
employment of boys, girls, and women in or about
mines ? (25)

3.	State the several requirements of the Act concerning
winding shafts. (25)

4.	Set out the several rules to be observed in sinking
pits. (25)

5.	What is the meaning of the term “ non-detonating ”
explosive, and under what conditions may such explosives
be used? (25)

6.	State the meaning of the word “ pressure ” as defined
in the general electricity regulations, and what are the
different pressure supplies mentioned in the regulations
and the voltage limits of each? (25)

{To be continued.)

Glasgow Enemy Coal Exporters.—The Court of Session
(First Division) disposed of a petition of the Board of
Trade for the winding up of Endemann and Company
Limited, 53, Bothwell-street, Glasgow, and the appoint-
ment of an official liquidator. The business of the company
was to purchase coal in this country for export to cus-
tomers in Germany, Belgium, Holland, Denmark, Norway,
and Sweden. The principal shareholder was Walther
Hugo Endemann, a German, who is understood to be resi-
dent in Switzerland. Only two ordinary shares were held
by subjects of British nationality and parentage, all the
others being in the names of Germans. The controller
has realised all the assets of the company, with the excep-
tion of debts due by parties in Germany and Belgium,
amounting to £9,816, the value of which is unknown. The
proceeds of the realisation amount to upwards of £15,000.
The petition was granted, and Mr. Rintoul appointed
liquidator.

Bradford Coal Merchants.—A meeting of the Coal
Merchants’ Section of the Bradford Chamber of Trade was
held on May 23 at the Chamber’s headquarters, under
the chairmanship of Mr. Joshua Smith. Mr. B. Galloway
presented a report on a recent visit of a deputation from
the Yorkshire Federation to the Coal Control Department,
particularly with reference to the proposed coal rationing
scheme. In the matter of military service it was reported
to the meeting that the local recruiting authorities were
not compelling men engaged in the coal distributive trade,
and who are affected by the new Military Service Act, to
undergo medical examination at present. Prior to the
meeting of the section the first meeting of the newly
reconstituted Bradford Coal Exchange was held at the
Mechanics’ Institute. Mr. Edd. Smith, a member of the
Coal Merchants’ Section of the Chamber, was elected as
president, and Mr. J. Whitaker was appointed hon. secre-
tary. The exchange replaces the old exchange, which was
held at a local hotel, and it is under the joint control
of colliery travellers and local merchants. The new com-
mittee comprises seven travellers and seven merchants.
Except in special circumstances nobody who does not hold
a membership ticket will be admitted, this being quite
a new feature, as distinct from the previous right of any
merchant who wished to buy from the travellers to attend
the exchange.