72 
THE GKOLOGIST. 
merits of tlie two systems of working coal ; but all must be agreed as to 
the importance of adopting the system that will admit of the greatest per- 
centage of " round " or " hand-filled " coal, and the greatest yield per acre, 
whilst affording to the workman the greatest security from accident, and 
the capitalist from losing his property. To say that any one system pos- 
sesses all these mucli-to-lbe-desired advantages, under all circumstances, is 
more than could be afiirmed. That the long- wall system possesses advantages 
over the pillar-and-stall, imder some circumstances, is an indisputable fact ; 
while, on the other hand, it is simply impossible to work some mines to 
advantage upon the long-wall system, however skilfully the workings may 
be conducted. Perhaps the most important advantage in the long-wall 
system is, that all the coal may be worked out without the slightest waste ; 
this cannot be said of any other. If we consider this loss or waste in a 
national point of view, it will not be of much less importance to the whole 
community or future generations than it is to the proprietors of mines who 
sustain a direct pecuniary loss ; for although there may be no fear of the 
coal of the United Kingdom being exhausted for a couple of centuries, 
— and in the meantime substitutes may be discovered that will lessen its 
consumption, and render the nation much less dependent upon it than at 
present, — it, however, cannot have failed to have occurred to all who have 
carefully considered the subject, that before another century has passed 
over, coal will not only be far more difficult to work, owing to the increased 
depth at which it will have to be wrought, but that some of our existing 
coal-fields will have been worked out, and many others reduced to very 
narrow limits. 
In working the coal upon a properly conducted system of long-wall 
working, where the mine is adapted for such system, there can be little 
doubt but that the risk of accidents from falls of roof is materially lessened. 
The author had never seen the slightest accident from such source, where 
the long-wall system has been practised. But the fact ought not to be 
overlooked that some mines are naturally more dangerous to work than 
others, and that the danger often increases in proportion as the thickness 
of the seam increases, assuming that all other circumstances remain the 
same, and that, as a rule, it is the thinnest scams that are worked upon the 
long-wall system. The ventilation is far more simple in long-wall work- 
ing than in pillar-and-stall, besides which, the health of the workman is 
not so impaired by driving narrow or " strait " work, this being in a great 
measure dispensed with. 
Another advantage for the long-wall system is that of being able 
to dispense with the necessarily large outlay consecjuent upon driving 
narrow work in a systematic manner preparatory to working back the 
pillars, and thus securing a return for the capital expended in the least 
possible time. The iXorth of England may be considered as the parent of 
the pillar-and-stall system, but it is now more or less used in almost every 
coal-field in Great Britain as well as upon the Continent. If it possessed 
no advantages over the long-wall system, the mining engineers who adopt 
its use might reasonably be considered very prejudiced men. That epithet 
has been lavishly applied by some of the advocates of the long- wall sys- 
tem to those who continue the use of the pillar-and-stall system, for- 
getting that they lay themselves open to the very same charge by adhering 
too rigidly to that which they believe to be the best. The author had 
deemed it best to carefully examine into every circumstance connected with 
a mine before adopting any system, and after so doing, he would not say 
that he might not err in judgment. The pillar-and-stall system will admit 
of an almost unlimited quantity of coal being daily worked from the same 
