1872.] ( 385 ) 
PROGRESS IN SCIENCE. 
MINING. 
Ir has often been remarked that the occurrence of colliery explosions is 
closely connected with certain states of the weather. A valuable paper on 
this subject has been read before the Royal Society by Mr. R. H. Scott, F.R.S., 
the Director of the Meteorological Office, and Mr. W. Galloway. After 
reviewing the evidence bearing upon this subject, the authors conclude that 
We are quite justified in maintaining that certain meteorological changes are 
proximately the cause of most of the accidents in our coal mines. The con- 
tinuous records kept at Stonyhurst Observatory furnished the meteorological 
data used in this enquiry. Curves for the barometer and thermometer were 
plotted for the three years extending from 1868 to 1870, while records of the 
colliery explosions during the same period were obtained from the Government 
Inspectors, either directly or from their published reports. On comparing the 
actual dates of the explosions with the corresponding meteorological records, 
it was found that out of 550 explosions 266 might be attributed to the state of 
the barometer, and 123 to that of the thermometer, while the remaining 161 
remained unaccounted for on meteorological grounds. In other words, exacly 
70 per cent of the explosions were directly related to meteorological influences. 
Some of the authors’ conclusions are of much practical value. Thus, they 
show that we must not always expect an accident to follow immediately after 
a fall of the barometer, but that in many cases explosions have not occurred 
until two or three days after the barometric column had reached its 
minimum. It appears that during violent oscillations of the barometer the 
number of explosions does not correspond to the number of minima, but the 
greatest number of accidents occur when a serious break follows a long period 
of fair weather. Elevation of temperature must, of course, greatly interfere 
with the natural ventilation of a colliery ; and hence, if a warm day occur ina 
cold season, when natural ventilation is relied upon, it is very likely to be 
followed by an explosion. For a like reason, the first hot days of spring are 
too often marked by colliery accidents. - 
A paper on increased safety in working coal was read by Mr. S. Firth, 
M.A., at a recent meeting of the Midland Institute of Mining Engineers. By 
carefully comparing the dangers incident to the present sy stems of w orking by 
“bord and pillar” and by ‘“ long wall,” the author concludes that the latter is 
by far the safer method. But although advantageous in many respects, the 
long-wall system exposes the collier to considerable danger from falls of the 
toof, from falls of coal, and from the use of gunpowder. Now, Mr. Firth 
argues that these sources of peril may be almost entirely removed if coal- ‘ 
cutting machinery be employed in connection with long-wall work: the miner 
is then no longer exposed to danger by falls of coal, the roof is much safer, 
and no powder is required. Hence the author advocates the adoption of the 
long-wall system coupled with the use of coal-cutting machinery, and believes 
that the danger of colliery work will then be limited to such items as could be 
readily held in check by strié attention to the Government rules. To use the 
author’s words, it may thus become “possible for miners to work and win 
coal without the operation being a perpetual fight for life.” 
To encourage inventors in improving coal-cutting machinery, Mr. Firth has 
liberally offered a prize of £500 for the machine which shall be best adapted 
for general use in coal and ironstone mines, and shall reduce manual labour 
toa minimum. The machines entered for competition are to work with com- 
pressed air supplied at a pressure of 50 lbs. to the square inch. It is hoped 
that this stimulus will lead to great improvements in coal-cutting machines, 
VOL. Il. (N.S.) ' 3D 
