Year: 1873

reached the Mississippi river, travelling East


ward, producing similar effects to those NOTED


in Central Iowa. At about % p. NJ. light
discharges from the Western wires were OBJ
served in the Chicago Office, but it was eyi-


dent that these came from a distance, and


that the storm had not Travelled far East OF


the Mississippi. These continued at inter.
walls during the night of the 7th, and until


the evening of the Sth, when the discharge.


became more rapid and of exceedingly high
tension. When the batteries were taken of
and both ends Of the line left open, if the
finger of an individual standing upon the
floor was presented in proximity to the wire,
an immediate discharge took place in the form
of spark, and when a number joined hands
and insulated themselves from the floor a
spark could be drawn from any of them by
any one standing on the floor 1t was now
evident that the storm had reached this To-
cality, and it was ascertained that it had
entirely ceased West Of the Mississippi river
Observations disclosed the fact that with two
or three exceptions the effect was confined to
wires running almost due East and West,
the exception being on wires running due
North from Chicago, on which but little in
| reference was noticed


Another singular fact observed was, on
some routes where number of wires occu-
pied the same poles one wire alone was highly
charged and so affected that to work it was
an impossibility, while all the others were
entirely free from any external influence. In
some cases the wire occupying the top Of the
pole would apparently receive the whole
charge in other eases the bottom wire would
receive it, and still in others the charge
seemed to be divided equally between all the
wires. In the Chicago Office the effect was
similar to that observed in Iowa, and every
observation confirmed the opinion that the
centre line of the storm was due East from
Des Moines. Iowa, to Detroit, Mich, narrow
ing in its limits North and South as it ap-
preached the latter place, where it arrived
on the evening of the Sth inst and rapidly
subsided. \ high wind, varying from TWEEN
ty y-eight TO twenty-five miles per hour, with
the same range of temperature as first noted,
accompanied the electrical storm from its in
ception in the West until it had passed Chi
cago, where the weather was clear and
bright, but the wind still blowing a gale.
This display was observed by a large number
Of operators and practical telegraphmen, and
all accord in saving that its effects were en-
tirely different from those experienced during
the ordinary auroral storms with which they
are familiar


At the Eastern sloTe of the Rocky Noun
tains a similar phenomenon has been fire.
quently witnessed upon a wire running North
and South, but rarely on an East or West
wire. As a high wind always prevails when
the effect Is experienced, many telegraph eX-
perts have attributed it to the friction OF the
wind, but this theory does notappear tenable,
from the fact that We so frequently have the
wind without the electric charge That the
electricity evolved by various processes accu-
mulatcs in the atmosphere and varies in
condition and intensity Is universally admit
ed. and that it is stronger in Winter than in
summer has been abundantly proved. Sir
Wm. Thompson has shown, by experiments
with the electr0meter. that during a wind
the air Is charged very intensely positive.
Now. upon the theory that the earth Is
charged negative to the atmosphere, there
must be a point at the surface of the earth
where discharge occurs or naturalization
takes place At points where the relative
humidity of the air Is very great, this Is
doubtless ever silently going on but during
seasons of intense cold, when the air Is nee
cessarily dry, the combination is evidently
rendered more difficult, and the tension there
by greatly augmented. If, under these circum
stances. good conductors, such a telegraph
wires. are interposed, they would certainly
assist in carrying a good part Of the atmos-
pheric charge to a point where the electrical
,ension was far less.


What the electrical conditions of the tele-
graph wires on the same poles were to render
one more susceptible of this inductiye intu-
ence than another, Is difficult to determine.
Or why wires running in other than East
and West directions should not have been
similarly affected is a problem we shall call
on our meteorological friends to assist in
solving. 1t is a fact, however, that their
resistance and insulation, as measured and
adopted a. standard of excellence in propa-
eating the electrical current Of the ordinary
yoltaic battery, did not assist in the least in
forming a theory. Should a recurrent storm
pass over this latitude, it is hoped that more
accurate and systematic observations will be
made and possible solution result.