The Sun.
London, England, 1861-02-01 00:00:00

- RISCA, THURSDAY.
The 'coroner r continued his rntitiiry yesterday,
after the despatch of our parcel, and resumed it
this morning.

Mr. Morgan Morgan,. at present manager of a
colliery in Somersetshire, and formerly employed
for about ten years in the Risca Colliery, which he
quitted in 1858, said he had been down the Black
Vein Pit. Entering first, and at great length, upon
the question of ventilation, he gave the results of a
series of observations which he had made for the
purpose of ascertaining the quantity of air passing
per minute into different parts of the workings
respectively.. He statecthis opinion was that the
current of air sent down .by the ventilating machine
was intermittent, being governed by the strokes of
the piston (the current created by furnace ventila-
tion being regular and continuous), while there
was a drag .upon the current in some parts arising
from the insufficient size of the air-ways and
return. The mode of ventilation in the Black
Vein he characterised ELS being of the most
primitive description, and ,he advised the
splitting of the air in numerous currents, each.
to travel a separate and independent dis-
trict, so as to confine the effects of an explosion to
the particular district in which it occurred, which
would make the pit as safe to work with naked
lights as it was now with lamps. He agreed with
some previous witnesses in tracing the original ex-
plosion to Sage's stall, or some stall near it in the
Fourth East Level, and thought with Mr. ilarri-
son the chief viewer of the pit, that subsequent
explosions followed. as the fire reached accumula-
tions of gas in other places.
. In reply to Mr. Evns, the' witness said he
thought ,it quite possible to work the Black Vein
'without powder, and'extremely undesirable to use
it where safety lamps are thought necessary. The
use of powder was, in itself a mere question of ex-
pense, and he had never seen coal that could not be
cut without it. •
In reply to Mr: Brough, the witness expressed a
decided preference for safety, or spare doors, over
canvas sheets. Being asked whether the system of
ventilation adopted in the Black Vein Colliery,
and which he had described as being. of the most
primitive simplicity, was not general in the neigh-
bouring valleys, he replied that there were few if
any pits in the neighbourhood of so fiery a nature as
the Risca Black Vein, and that, just in proportion to
its fire-generating properties should be the care
directed to prevent the accumulation of gas in
a coal mine. He declined to commit himself
to express any conclusion with regard to the cause
of the accumulation of gas in/Sage's stall, to which
he and other witnesses traced the explosion, but
unhesitatingly asserted his conviction that there
must have been a rapid series of minor explosions
following the great or primary
_explosion, and aris-
ing from aCcumulationi of gOzreviously lurking
in the workings—decidedly opposing"the theory of
Mr. Harrison, that the secondary explosions were
caused by the contact of the flame of the first ex-
plosion with various bodies of gas set free by falls;
from the roof, those falls being occasioned by the
concussion. In support of his own view on this,
point he said the fire of the first explosion would
pass before the falls took place, so that it could not
airactuallythe tsoa om neer
titheep aa reach
theretoh
fe
p pure
wouldr gasese e
an e
rwbn newly
esbteette free,ad
properh
hydrogen,
dogen that
to
intervalat
to allow of a sufficient admixture of atmospheric
t
air, viz., three or four parts of pure atmospheric
render ignition possible. Finally, in reply to Mr.
Brough, he said that yeam ago, when in the ser-
vice of the company, he recommended the working
of a new pit to the Black Vein, in order to improve
the ventilation.
The cross-examination of this witness was still
proceeding when our report left.