coal trade bulletin - Clpdigital.org

48 THE COAL TRADE BULLETIN.
attaining a potential above that of the rail, and
no shock could be received.
Another source of danger is equipment that is
not intended to carry current becoming charged
by defective insulation, or otherwise. This
DANGER COULD ALSO BE ELIMINATED,
at least to a great extent by connecting the conducting
material of all such apparatus with the
earth.
One other danger to be taken into consideration
is the practical joker who connects up some innocent
looking piece of equipment with the live wires
and waits to see the fun when some fellow employe
receives a shock. The writer at one time
saw a workman receive a severe shock when he
attempted to take a drink of water from a tin cup
that been connected with a live wire. Such practice
should be frowned upon and the guilty party
severely punished.
It might be as well in a paper of this character
to consider ways to rescue victims of shock. It
is essential that the victim be removed from the
current-carrying conductors as soon as possible.
If the switch is near at hand it is no doubt best
to cut off the current, as the patient in contact
with the live wire will transfer current to the
rescuer if he puts himself in the line of passage
of the current. If the current cannot be cut off
quickly use any of the following ways: By prying
off with a dry stick. Possibly the handle of
a pick, axe or shovel would be best as dry wood
in a mine is not easily to be had when wanted
suickly. The trolley wire may be short-circuited
with the rail by throwing a crow-bar or a drill
across them. Great care should be observed in
this manner of rescue, for if the iron does not
leave the hands before touching the trolley wire
the rescuer himself will receive a shock, or the
hands of the rescuer may be insulated with dry
clothes or otherwise, and the victim removed by
jerking. If possible he should be removed by
one motion, as rocking back and forth w-ould only
increase the shock and burns. Some authorities
teach that it is best to use the feet and not the
hands to
PUSH THE VICTIM
from the wire. No doubt this is a good method
if it can be used, for in case of shock to the rescuer
the current would pass from one foot through
the legs and the other foot to the ground and
would do little injury since the heart and the important
nerve centers are not in its path.
As soon as the victim is rescued, if he is unconscious,
artificial respiration should be performed.
This should be kept up at least an hour or until
the patient is breathing freely.
Authorities differ greatly as to the best method
of artificial respiration. Until late years the
Sylvester method was used in the majority of instances,
but recent tests seem to indicate that the
Shafer or prone method is the most efficient.
Often in electric shock severe burns or even broken
limbs are sustained, and in cases of this kind
the character of the injury determines the method
of artificial respiration to be used.
The Sylvester method of artificial respiration is
performed as follows: First pull the tongue far
out to clear the windpipe, and hold by tying over
the tongue and under the chin. Kneel above the
patient's head and hold his arms just below the
elbow. Draw the arms outward and upward
gently and steadily and hold them as far as they
• ill go above the head for about two seconds.
This motion opens and expands the chest to the
greatest possible extent. This is due to the fact
that certain muscles are attached to both arms
end ribs ancl when the arms are raised these
muscles raise the ribs and so enlarge the chest.
Then bring the arms down till the elbows press
; gainst the chest; a little pressure will
DIMINISH THK SIZE
1,1' the elastic chest as much as possible. Do
this for about two seconds. Continue these mot'ons
about 16 times per minute.
In the Shafer or prone method the patient lies
iace down. The operator kneels astride the body
end places his hands across the lowest ribs and
swings his body forward and backward so as to
allow his weight alternately to fall on the wrists
and to be removed. In this way hardly any muscular
exertion is required. The size of the chest
' eing diminished forces the air from the lungs.
The elastic chest then springs back and the air
enters the lungs. The rate for this method is
c.lso 16 times per minute.
We will probably never know- just how many
of our mine fires and explosions have been caused
by electricity, but we do know that fires and explosions
are possible (to what degree they are
possible depending, of course, on other conditions)
when the workmanship or the installation is defective
or equipment is injured by falls of roof
i v otherwise. Incandescent lamps may ignite
i ombustible material if placed in close proximity
*. ith them. The blowing of an open fuse may
produce heat and flash enough to cause a flre or
explosion, or even switches may produce sparks
enough to be dangerous.
It is poor practice to use feeder wires that are
insufficient in size as the over load might cause
heat enough to soon destroy the insulation. A
leak to the coal or across timbers may follow and
a fire result.
Possibly the greatest danger, however, is the
fall of roof destroying the trolley line. With this
in mind we