110 
Journal of the Mitchell Society [. November 
steeper and shorter and go in a smaller space. The men will 
always ride up in a bucket, fitted with a crosshead running 
in proper guides or running in a closely planked compart- 
ment if the shaft is crooked. Therefore, the ladderway is an 
emergency exit only and a good, continuous vertical ladder 
securely fastened against one wall of the compartment is all 
that is needed, and the compartment for ladder and pipes 
may seldom need be over 3 by 4 feet. The two compartments 
and the division between them then need be only 4 by8 or 2>% 
by 7 feet inside. Besides being much more cheaply and 
rapidly sunk, the small shaft need not be so heavily timbered, 
since the shorter timbers are stronger and the earth pressure 
tends to arch around the shaft instead of coming fnll upon 
the timbers. On the other hand, the first 6 by 10 feet ( 8% 
by 12% feet outside timbers) shaft at the Montgomery Mine, 
at Candor, Montgomery County, became useless after about 5 
years from the buckling of the timbers, although splendidly 
timbered with 12 by 12 inch oak sets, which showed no signs 
of decay. 
There is, of course, very seldom any need for more than 
one hoisting compartment, since the saving in power will 
only pay for the greater expense of engine and shaft when a 
large amount of ore is to be hoisted from considerable depth. 
When a single large skip will handle all the ore, there is no 
need of putting in another to remain idle half the time. 
Timber framing for shafts and tuunel sets is often unnec- 
essarily complicated and the carpenter must waste mnch time 
chiselling, when simple notches laid off with a square and 
cut by saws are often stronger and always more easily made. 
The most disastrous error is usually great haste in putting 
in a mill or smelter. It seems that the first thing that many 
miners think of after finding a little good ore is to stop work 
in the mine and put in a mill; so there are mills which have 
been able to run less then a month before the mine was ex- 
hausted. There is usually a neighboring mill to which tha 
ore might as well have been hauled. It is seldom that tests 
are made to tell what sort of a mill and treatment is adapted 
