The Memphis appeal. [volume] (Memphis, Tenn.) 1886-1890, 1888-02-10

III n current OF electricity isslarted In the
wire A Ii toward u, current will be In.
duccd into the wirc q ID, which will flow
toward q that is opposite TO tho other
current. II the current in A b IL stopped,
current will be induced in the wire o u
flowing toward ID. Thus for every current
sent in A b there will be two currents in
duccd In q d, but they will be only mo.
mentary. II the current flows steadily in
A u, there will be no current induced In
G II. II the current in A b rises orialls or
decreases without stopping aliogctherJ
currents will DO induced in q ID rs before,
though not quite 30 strong. Wherever
and whenever q current Of electricity IN
started, whenever il varies in strength
there will be induction in any and all con
tiguous bodies be they wires, walls or what
else. Induction is an inscparable accom-
panimcnt Of electricity in motion.
''The electricity flowing from a galvanic
battery or dynamo machine extraordinarily
intermittent, practically the current from
either source Is considered continuous
There are many causes 90 mako Il inter.
mittcnt and variable. in the dynamo.
The electricity produced from the copper
bar revolving in front OF magnet in the
dynamo Is collected at the commuiator by
what Is called brush. II the brush fails
10 make contact with the bar, which IL nc
Volving at the rate OF 200 10 1000 revo.
luiions per minute. for every failure there
j. an intcrmiesion or variation, 10 one dc
1cctiyc bar in the commutator would pro.
duce >, 400 10 1900 induction currents per
minute. II the engine driving the dyna-
mo runs irrcgularly from varying steam
pressure, or the slipping Of belt or any
cause whatever, there Il variation In the
strength OF cnnpnt sent out and innumcr.
able induction currents produced in any
conductors near the light wins. Even
when the light nickcrs from defective car.
hons, or from bad adjustment Of the car.
bons, induction will result, because current
varies with the light.
Escape or leakage il more easily man.
aged aud, unless In extreme bad weather,
l. only q temporary difficulty. In the
electric light system what IL called me.
tnllic circuit Is used; that II, the wire starts
from the station out through town and ne.
turns 10 the station. Now II this wire
iAlls on the ground on makes connection
with the ground nj any one point along its
route, II viii have no effect on the current,
because the earth viii not take electricity
from conductor NJ one point unless II can
give back 10 the same conductor at some
other point an equal quantity Of elec.
tricity.
Glass and porcelain and wood arc good
insulaior when they are dry. But when
n film Of water forms ON glass or porcelain
II will conduct more or less electricity. II
q speaking wire and light wire are carried
ON the same poles or supports, obviously
the wir carrying the larger current will
leak Into the other. Now leakage Mt one
point, NJ has bccn shown, has no effect;
but II there are many points Of the wircs
run ON the same supports for a considen,
bile distance, there will be pfoportionat1
leaking which will affect the speaking
wines directly by leakage, aud indirectly
by induction. For when the leaking on
light wires Is considerable, the dynamo /,
unable 10 supply the loss, and ~ leakag,
u very variable, the effect ON ncighborins
wires ia variable, both from induction and
escape. In this condition Il Ia difficult e
distinguish them, but leakage IL compare
lively steady, and often will not change loi
several minutes n a time, while induction
l. always intermittent. Generally IN,
mysterious agency Is blamed ior ever,
trouble, while the guilty leakage Is allowed
20 escape"
he committee can now get together
again and Put al things In their proper
shape, thanks 10 Mr.. flannery.