Evening star., 1901-04-18

mirage himself, but he refers to the mar
vicious tales which he has heard, more
pecially about their appearance in the arc
tic regions, and declares that he is pre-
pared to believe them.
The Theory of Mirages.
Practically all writer's on the theory of
the mirage hold that, while the images pre-
sented to the observers eye may be distort-
ed and obscure. they have certain basis
In fact They are representations accurate
or tnaccurate) of real things. Napoleons s
army. crossing the; sands of lower Egypt
saw remote villages which were yet below
the horizon lifted into view. At sea 1t is
not uncommon to detect ships that are yet
too far away to be seen normally. Indeed,
there are multiple images, above the
other, and some of them upside down, per-
haps. But in spite of their eccentricities
there is a real ship involved in the phe-
nomenon.
In some mrages there Is great magnifica-
ton of the objects seen, but only in a vertf
cal direction. The passage just quoted from
Scoresby illustrates the point in measure.
This effect is closely allied to the apparent
lifting of scene above its true position, or
what sailors call looming For instance,
a mirage once showed people at Hastings,
England, the French coast near Boulogne,
forty or fifty miles away. The curvature Of
the earth is here sufficient to hide one city
from the other under ordinary conditions.
Prof. J. d. Everett of Belfast, Ireland in a
lecture delivered over a quarter of CEN
tury ago dWelt at length on the false ideas
of nearnesS and the distortion of form that
results from looming. This vertical mag
MITIGATION is shown in cliffs and icebergs at
sea- said he, land produces an effect of
ptnnacles. spires. columns or basaltic cliffs.
The magnificent columns which con-
stftute part of the Fata morgana "a mi
rage in the Strait of Messina are in like
manner to be attributed to vertical magni-
fication. An appearance of the same kind
known as the Merry Dancers is often
seen by boatmen off the Giants Cause
way"
Said to Resemble Bristol.
In his book on Alaska mines Bruce says
that the 'Silent City, has been identified
as a view Of Bristol, England But 1t is
possible that he has somewhat hastily ac-
cepted some one elses conviction on this
subject. At any rate there are several rea-
sons for demanding further evidence. It is
doubtful whether any object shown In a
mirage was ever more than fifty or a hun
dred miles from the observer and in many
instances 1t has been much nearer. From
DR.. Ftlippis account of the experience of
the Duke OF Abruzzf party 1t is evident
that a line Of hills only few miles away
afforded the basis of what they beheld. Mr.
Bruce mentions the popular suspicion that
Willoughbys picture was a fake" and
adds that he himself was under such obIi-
cations to the prospector that he could
hardly confess the truth II he had any
doubts Of his own. Hence any. fancied re-
semblance between that photograph and
Bristol will not count for much. DR., Film
PTS book contains no representation of the
Silent City," although it is full OF other
photographs of Alaskan scenery Perhaps
the image was too unsteady for camera
to register 1t. If the Vancouver expedition
brings back well-attested picture that
looks like Bristol, one will be justified i'm
taking stock in the notion of identity But
untn tnen 1t Is wiser TO suspend judgment
or to discredit the idea altogether. Indeed.
the phenomenon Is enough of a marvel
without any such assumption.