Ccrllhrg ^fplosions. 
By E. WETHERED, F.G.S., F.C.S. 
T he frequent recurrence of explosions in collieries has 
become a matter of such grave importance, that the 
question of what is to be done to prevent these disasters demands 
serious attention. 
Not that the subject has been neglected ; the “ Mines’ 
Regulation Act,” passed in 1879, contains provisions with a view 
to prevent these explosions by directing certain precautions to be 
taken in mines which contain explosive gas. The number of 
Her Majesty’s Inspectors of Mines has been increased, and care 
has been taken that they should be properly qualified men. 
Notwithstanding these precautions explosions continue to occur, 
accompanied with appalling loss of life. 
In order that the subject may be made clear, I propose to 
give an outline of the facts of the case. 
Coal is the product of decayed vegetation which lived and 
died countless ages ago. As the result of the decomposition of 
the vegetable mass, there would be evolved, among other pro- 
ducts of decay, a gas known as light carburetted hydrogen or 
fire-damp, and it is this with which we have to deal as the chief 
factor in colliery explosions. 
Chemists look upon matter as being made up of atoms and 
molecules,^ and it is by the exchange of these atoms according 
I An atom is the smallest portion of matter which can enter 
into a chemical compound, whilst a molecule is the smallest 
quantity of an element or of a compound which can exist in the 
free state. 
