244 
2iid. Economical ventilation, and increased safety to the 
miner. 
3rd. Simplicity, and less liability to accidents ; and — 
4tli. An increased quantity of useful Coal from the same 
area. This is the national gain all desire, and which, the 
writer believes, will be best obtained by the diffusion of im^ 
proved mining knowledge concerning such a system, rather 
than by legislative interference. 
To our local friends in the neighbourhood of Doncaster, 
the economical working of our Coal field is a matter of 
great interest, standing, as at present we do, upon those Coal 
measures underlying the Permian Eocks, a section of which I 
have added to my illustrations, calculated from what I con- 
sider the most reliable data ; their value and extent may be 
estimated by one fact, viz., that in this section are repre- 
sented all the seams belonging to the Yorkshire Coal Field, 
numbering nearly 40, with an aggregate thickness of nearly 
90 feet, at least 30 feet of which will be workable sooner or 
later in this district. 
Those seams underlying the Permian formation, alreadij 
worked, I have distinguished on my section, and also added 
the locality where such Collieries are situate. 
The above rocks will have to contribute the Coal Fields of 
future generations ; at the same time, situated as the upper 
portion of this Coal field is, within a practicable depth, I do 
not see any reason why it should not contribute its share to 
the requirements of the present centurj-, and I express my 
astonishment that it has not already been developed, and 
thus locally derive the advantage of the excellent colliery 
sites which are to be found in the vicinity of Doncaster. 
My own opinion has been confirmed by a friend of mine, 
of great commercial experience in the Coal trade, that Don- 
caster is unequalled in its Geographical position by any col- 
liery district in the kingdom. With a willing and liberal 
