565 
It would appear from the statistics of our last census, that 
of the population of Great Britain, about 220,000 of our 
fellow-countrymen are now pursuing the occupation of coal 
miners. And from the vast stimulus given to the trade, as 
well as from the progressive exhaustion of the shallow seams 
of coal, in every part of the country, an increasing risk is 
gradually accruing to this vast and industrious body of men, 
which claims for its amelioration the best efforts of intelligence 
and science. 
It is not intended to deny, or even to overlook, the 
numerous and powerfully directed efforts both of Govern- 
ment and scientific bodies, and individuals, to diminish, if 
not altogether obviate, the hazardous conditions under which 
the occupations of our mining population are followed out ; 
on the contrary, I do not think that much would remain 
for the severer deductions of abstract science, if the full 
benefit were derived from what has been already done and 
published, for revealing the real nature and character of the 
difficulties to be encountered, and the most probable means 
of surmounting them. The researches of Faraday, Playfair, 
Graham, De la Beche, and Phillips, not to mention the 
names of many practical mining engineers who have laboured 
so nobly in the field, afford an abundant guarantee for this 
assertion. But the grand object to be attained is the applica- 
tion, in individual examples, of a sound principle of working 
in harmony with the knowledge we now possess, both of the 
agents which surround us with their mischief, and of the 
laws which those agents acknowledge, in order to their being 
placed more effectually within our control and command. 
It would be presumptuous in a paper of this kind to 
attempt the definition of any plan or system of working, 
which should be supposed equal to the test of special and 
individual application. To a considerable extent every 
colliery requires a system of management adapted to the 
