Mower County transcript. [volume] (Lansing, Minn.) 1868-1915, 1888-09-05
AN IMPORTANT MATTER.

AN IMPORTANT MATTER.
Notwithstanding Said to Be ; Preventive
OF snow-Bllndness.
As q partial answer. to Prof. Bay
Lankester's Inquiry on nose-blackea-
Ing as preventive Of snow-blindness,
may offer some observations which
have made in my many wanderings in
the higher Alps in early summer, when
1 have necessarily had much expert
ence of the effects of snow on the hui
man body.
But first I should like to draw ut
tention to letter of Hon. Ralph
Abercromby, relating some expert
ences on nose and face blachening in
Morocco to prevent sand glare, In Fiji
to prevent water-glare, and in Sikkfm
to prevent snow-glare. 1t was curious
that the Fjians. who ordinarily paint
ed their faces white and red tor orna-
ment, would, before going fishing ON
tho reefs in the full glare of tho sm,
blacken them. Mr.. Il Aher,cromby
draws attention naturally no 1.-The
strange anomaly of physiolog-
ical experience apparently con-
tradicting the teachings of pure
physics. Charcoal black, which is
used in physical experiments as the
best absorbent of every kind of heat
radiation, is practically used by three
races at least to protect one of tho
most sensitive human organs from re-
Elected light and heat" @ g.
Experience has. I think, sufficiently
shown that snow blindness and Snow
bum, or sunburn on snow, own tho
same causes for their production; and
as nowadays both guides and climbers
in the Alps invariably take the precau-
ton of protecting their eyes with COL
ored spectacles, snow-blindnesso is
rarely heard of. My observations sro
almost entirely confined to the causes
of sunburn. -" r. ~.
1t will, I think, be readily conceded
by Alpine climbers that sun ON tho
snow burns more quickly than ON rocks
or in the heated valleys at a lower ele-
vation. This increased power of burn-
ing appears somewhat singular when
one rejects that the heat rays must be
occupied in the melting of the snow
and thus rendered latent.
, Ir0n-E0rkers, glass-workers and
others are constantly exposed to
heat of 400 deg. or 500 deg. F. and yet
do not become burnt; and there can be
little doubt that the enormous radiation
from heated rocks and valleys, in adj
dition to the direct rays of the sun,
makes up an amount of heat far great
err than is ever experienced on even a
sunny snow slope, and yet one does
not become sun-burnt. No doubt the
surface of the Snow reflects and dis
perses much heat, but certainly far
less than it receives, as heat rays are
absorbed and rendered latent by the
snow melting and evaporation. Ex-
perience fully corroborates this, for
one may often lie on ones back and
freely expose the face for long periods
to the sun and yet remain unburnt.
There must, therefore,, be some other
factor in sunburn than heat alone.
In discussing the subject with Prof.
Tyndall he added the interesting and
fact that he was never more
burnt on snow than while experiment.
ing with the electric light at North
Foreland Lighthouse, where there
was no heat sufficient to produce such
an effect.
am aware that sometimes, in Pc
culiar conditions of the atmosphere,
the direct suns rays will burn. have
met with some singular instances where
several persons have been burnt on the
same day, even in England, who had
never previously suffered in that way.
I am further aware that sometimes |
(not always) in dead calm on ships
deck one may be severely burnt, and
that in boating on a river the same may |
happen. Masks and walls |
have been long used as a protection on
snow, and ar, more or less successful,
brown walls and glasses in my expert
ence being the most efficient. As bear
ing upon this 1 may mention that a
fl lend of mine after an ascent on snow
had an enormously swollen face, and I |
observed that in the general swelling
there were many pits or depressions,
and that each pit correspondent to a
freckle. The irritating rays had been
intercepted by the brown color of the
freckle. About the same time I en-.
countered a paragraph in the London
Lament saying that German savant |
had been experimenting on the effect
of sunlight on the retina, and had
found that it had destroyed the visual |
purple of the retina, but that the action
was modified by transmitting the SUMS
rays through various colored glasses,
and that when transmitted through |
brown glass the purple of the retina