173 
been principally used as a stationary power ; but tlie writer 
believes it is not impossible that at some future time, air 
engines underground will there supply the same place as 
locomotives do on the surface on our railways, and must 
ultimately be used for conveyance of passenger and goods 
traffic in all large towns. 
Another very valuable system of haulage, of recent in- 
vention, is that of the wire tramway ; this is, however, not 
applicable for underground purposes, but is peculiarly useful 
on the surface in undulating and hilly districts, where it is 
required to convey minerals over rivers and valleys. 
In the lighting of mines, there has not been that marked 
improvement one might have expected from the progress 
made in other departments of mining industry ; for the onl}^ 
improvements since the Safety Lamp introduced by Sir 
Humphrey Davy, in the year 1816, are matters of detail in 
construction, securing more perfect means against the lamp 
being tampered with by the workman, and such modifica- 
tions as the lamps of Mueseler and DubruUe. The lighting 
of mines is still imperfect, and affords the very best field 
for invention. The writer looks forward to the time when 
this problem will be satisfactorily solved, and the light in a 
mine be so good, as to render it unnecessary that lamps 
should be carried about or suspended; involving, as this 
practice does, the greatest risk to life and property. 
Safety in the lighting of mines may possibly be secured 
by paying more attention to ventilation, and placing less 
reliance upon lamps for safety, and as one means possible, by 
the introduction of an Exhaust Fan, or other arrangement, 
for boring or draining off the gas in a coal seam, and storing 
it ill reservoirs, as we do with water, and utilising it for the 
purpose of lighting, somewhat after the manner proposed 
by Mr. Falkner, of Manchester, the inventor of, probably, 
the best-known system of electric signals for undergi'ound 
application. 
