r 468 J : 
XCVI. Intelligence and Miscellaneous Articles. 
VENTILATION OF COAL-MINES- 
We have already alluded to Mr. Ryan’s improvements 0D this 
important subject, and we are happy to state that they have 
heen rewarded by the Society of Arts, by a vote of one hundred 
guineas, and the gold medal, the highest premium ever yoted by 
the Society. 
Our readers already know that the most dreadful accidents 
which happe® in coal-mines, and those of most frequent occur~ 
rence, arise from explosions occasioned by the accumulation © 
hydrogen 25> and the defective means hitherto adopted of cat- 
rying off that deleterious and highly inflammable substance. 
Mr. Ryan’s method of ventilation obviates all these dangers, 
and carries off every particle of the hydrogen 885 the instant it 
3s liberated from the coal. His first operation “s to insulate the 
whole mine, OF field, as “+ js technically called, by cutting roun 
st a course oF passage This is what he calls his gas course 5 
and it is always made of a size sufficient to carry off all the gas 
which would otherwise accumulate in the mine. Within the 
body of the mine itself, holes are cut of different diameters, €n- 
tering into this gas course from the higher parts or roof of the 
mine. Between this gas course and the lower part of the up- 
cast shaft of the mine, 4 communication ‘5 made, and the gas 
by its levity naturally ascends. Heat, however, is occasionally 
applied at the lower part of this shaft to accelerate the exit of 
the gas. Our philosophical readers must be aware that no mine 
whatever can produce the quantity of hydrogen which a gas 
course on this principle is capable of discharging- In fact, on 
the old system of ventilating by the labyrinth process the at- 
mospheric air remains at least twenty hours in a mine of com 
mon dimensions, during which it traverses a space of forty miles, 
and becomes every second more and more impregnated with hy- 
drogen gas, and consequently increasing the danger throughout 
its whole passage through the workings of the mine. On Mr. 
Ryan’s system, the inflammable gas, as fast as it flows from the 
workings, takes the nearest course to the upper gallery or reser= 
voir for gas, whence it finds its Way by the shortest course to 
the upeast shaft, through which it passes ‘nto the open ait 
Mr. Ryan has introduced his valuable discoveTy with the hap- 
piest results into some of thé most destructive and fiery coal- 
ines of Staffordshire and Worcestershire, aud has obtained cer= 
tificates of the most. flattering description from numerous Ter 
spectable and humane mine-owne!ls- In some mines in Wor- 
cestershire, for instance, where daily explosions take place, and 
where none but the most desperate characters could be obtained 
' as 
