seems
to be little in common be-
tween the lights seen by the
writer and St. Elmo's fire as
usually described. In a second
letter to Dr. Abbot, dated
January 9, 1920, Professor Perry
states the case clearly when he
says, "My own impression of St.
Elmo's fire and similar phenom-
ena was that it occurred at the
extremity of some solid conduc-
tor instead of occurring, as in
the case of the Brown Mountain
lights, in the air, at a great
distance from any object."
8. Andes light: The name "Andes
light," according to information
furnished to the writer by Dr.
Herbert Lyman, of the U.S.
Weather Bureau, is given to a
very striking luminous discharge
of electricity seen over the
crest of the Andes in Chile,
where ordinary thunderstorms are
almost unknown. The mountain
peaks appear to act as gigantic
lightning rods, between which
and the clouds silent discharges
take place on a vast scale.
The principal writer on the
Andes light is Dr. Walter
Knoche, who was for several
years director of the Central
Meteorological and Geophysical
Institute at Santiago, Chile,
and who says that he has seen
this light at distances greater
than 300 miles. Most of the dis-
charges appear to produce glim-
mering lights that have circular
borders. The flashes are bright
at their starting points but
diminish rapidly in intensity
and then slowly disappear. The
area of this silent discharge is
at first small and lies over the
main cordillera. but it soon ex-
tends far over the zenith and
sometimes reaches over the coast
cordillera and out to sea. The
phenomena is best seen in a
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clear
sky.
Dr. Guy Hinsdale, in the
Scientific Monthly for September
1919, reports that in western
Virginia, where there are "nu-
merous parallel ridges with
intervening deep and narrow val-
leys, it occasionally happens
that an electric discharge takes
place from the summits of these
ridges into the atmosphere.
There is nothing audible, but
merely the sudden glow of the
higher clouds in the dark, night."
The appearance of the Andes
light, as shown in illustrations
given by Dr. Knoche and in the
accounts of it already cited, is
totally different from that of
the Brown Mountain light as seen
by the writer during his inves-
tigation or as described by
others, and there appear to be
no geologic conditions at or
near Brown Mountain that would
produce electrical discharges
there rather than at Blowing
Rock or Grandfather Mountain or
any other prominent point in
this region.
9. Mirage: Mr. H. C. Martin, in the
Lenoir Topic for April 19, 1916,
and afterward in conversation
with the writer, has suggested
that the lights may be due to
mirage. He thinks that air cur-
rents of different temperature
and density may produce between
them reflecting surfaces, from
which bright stars or other
lights might be reflected in
such a way as to produce the
effects commonly seen. According
to this explanation the wavering
of the reflecting surface would
cause the sudden appearance,
wavering, and disappearance of
the light.
A mirage is a phenomenon of
the daytime rather than of the
nignt. The requisite conditions
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