February 6, 1914

THE COLLIERY GUARDIAN.

299

have changed and placed it out of compliance in
some detail. In some of these regulations there was a
saving clause “ as far as was reasonably practicable,”
but nearly every one might in itself be held to be
reasonably practicable, but when there was so many
things to do it was the number that rendered to the
ordinary man some of them not “ reasonably practi-
cable.” Then, again, every great disaster produced a
crop of recriminations. The great cure offered now
was “automatic safeguards”—all well-meaning; some
under certain conditions useful, many absolutely
impracticable or only of very limited use. He thought
experienced persons would bear him out in saying
that nearly every “ automatic safeguard ” to meet one
risk carried with it the introduction of other
risks in itself or increased the risk of other
existing dangers, and it was there that expert opinion
came in—judging the relative risks in each case. He
mentioned as one example their old friend “ Underground
pipes.” Last week a leading London paper published
an article dealing with gas in mines. The points were
briefly these : Why trust to an examination of the mine

Personally he had great faith in the efficacy of stonedust.
His own doubt was as to the applicability of it to
the heavily-timbered roads with the bad roofs in their
collieries. He hoped that doubt would be removed,
and that no one would condemn it before trying it.
He trusted, however, that the G-overnment would
not legislate until it had been proved to be efficacious.
There was another phase of the coal trade, which
occupied a great deal more of their time and attention
than they liked He might say that it occupied more
than its legitimate share of the time and attention.
He referred to the labour question. He thought the
position of labour politics in South Wales was
rather an unfortunate one at the present time.
There was a strong body of very advanced theorists
without very much practical experience who had been
able to impose their views on the older and more expe-
rienced men, and had got them to espouse causes which
they knew could not possibly succeed. The end of
the present Conciliation Board agreement was fast
approaching, and some time next year a new one would
have to be initiated. The South Wales Miners’

REVERSING THE VEHTILATJOM.

The Keith Mine Fan.

In accordance with section 31 (3) of the Coal Mines
Act, 1911, adequate means must be provided and main-
tained for reversing the air-current. Most of the leading
makers of ventilating machinery have now devised
methods whereby their standard fans may be adapted
to this purpose. Whilst not differing greatly in
principle, these plans are to some extent influenced by
the particular design of the fan used. The drawings
shown herewith illustrate a typical arrangement sug-
gested by Messrs. James Keith and Blackman Company
Limited, in connection with their double-inlet mine fans.
Its nature will be readily understood by reference to the
drawings, which show a longitudinal section, cross-
section and plan respectively.

It will be seen that the evasee chimney, which is
situated on the drift side of the fan, is provided with a

Fig. 1.—Longitudinal Section	Fig. 2.—Cross-section.

Fig. 3.—Plan.

BALANCE WE ICHT
AND REVERSING
GEAR

//

//

"'1

Figs. 1, 2 and 3.—Arrangement for reversing the air-current.





by firemen ? They were human, and might err. Lay
in pipes from the surface to the various places in the
mine, and collect samples of the mine air in the office
for automatic analysis, or attach them to the German
firedamp whistle which had recently been approved by
the Emperor William. To be of any use there must
be over 500 to 1,000 miles of pipes, requiring examina-
tion of all joints, to be kept airtight. Special shafts and
airways would be required to get them to the surface.
Mine managers did not object to good criticism, but
they liked to feel that those who criticised and gave
judgment had the knowledge and sense of proportion
which could not be obtained from books, but only came
from actual and sometimes painful experience.

Mr. Evan Williams, chairman of the South Wales
Coalowners’ Association, also responded. Referring to
the Senhengydd disaster, he said what they wanted to
find was some means whereby that ignition might be
confined to the body of gas present at the time and
prevented from spreading throughout the workings.

Federation, with a unanimity that could only be sur-
mised, had promulgated a schedule of rates which would
sweep away all the existing prices. It was stated that
the acceptance of this schedule was to be a condition
precedent to the signing of a new agreement. In his
humble opinion, they were making a great mistake.
They were raising expectations in the minds of the
workmen which they must know could not possibly be
fulfilled. These promises might for the time being add
to the numerical strength of the Federation, but when
it came to negotiation he thought they would find
obstacles and hindrances in the way.

Mr. A. K. Reese replied for the iron and steel trades.
He claimed that both iron and steel were necessary to
the development of civilisation. The railroad was one
of the most notable examples of the greatest civilising
agents yet produced.

Mr. W. D. Wight proposed the toast of “ Our
Guests,” and the Mayor of Merthyr briefly
responded.

hinged section, or reversing damper, which can be
raised by a counterweight in such a way that communi-
cation is opened up direct with the fan drift. At the
same time, by means of air-lock doors, the fan-suction is
placed in communication with the external atmosphere.

In this fan it is the runner which commands the
greatest attention, as in many respects the Keith fan
runner appears to have unusual claims for mine work.
The accompanying half-tone reproduction from a
photograph of a Keith double-inlet mine fan runner
clearly illustrates the characteristic features of this
type. Perhaps the most noticeable feature is that the
external periphery of the runner does not form a
parallel drum, but is smaller in diameter at the middle
than at the inlet ends a***J^b]ades. This construction
has been adopted in J ^^eompensate the tendency
of the air entering feeeyes of the runner to bank-up