Evening star., 1931-12-11
INVISIBLE DEATH
PHOTOS RECORDED
Algai Killed by Violet Rays
Form White Pattern
on Negatives.
rY THOMAS r. HENRY.

invisible Death taxes It's own photo
graph on living plate.
This strange phenomenon was shown
for the first time yesterday at the an
nual meeting of the Board of Regents
Of the Smithsonian Institution.
An ordinary glass plate is covered
With live algse, extremely minute water
plants, so they form a complete flm
over the glass. Then different wave
lengths Of the invisible ultra violet light
are allowed to fall on this plate. II
they fell on a regular Photographic
plate they would be recorded by black
lines which would become white on a
print. On this plate covered with liv-
ing organisms they are recorded by
white lines
Death Photographed.
These lines are the dead algae, killed
by the lethal. invisible rays. They
change color when they die. Not only
does this living plate represent a
weird sort of photography, but it illus
trates vividly upon what a slender mar
gin Of safety life on earth depends. 1t
might not require much of a change
AZ A1llA4t1Ollo Vi JA4E upPCl dbillIok)llCiC
for the surface Of the earth itself to
become just such a Photographic plate
with the whitening bones Of men and
animals making the white lines.
The ultraviolet lines that kill the
slgae come from a mercury lamp
Plenty of them are sent out by the
sun, but they never reach the surface
Of the earth where they can do damage
Far up in the sky they are stopped by
a blanket OF ozone. This shuts out
the ultraviolet just at the point where
1t becomes lethal. If there were a little
less ozone, so that these rays could get
through, life as 1t exists on earth prob
ably would be impossible. If there
were more Of It, so that the longer
ultraviolet rays also were stopped, the
health of plants and animals would be
seriously affected.
The Smithsonian regents also saw
for the first time new kind of brass
BRAIN" designed for a specific sort of
extremely laborious and complex mathe-
matical computations. The machine is
the invention of DR.. Charles G. Abbot,
secretary of the Smithsonian, and Is
designed especially to discover and
evaluate periodicities In a long series
OF observations-such as those Of solar
radiation or Of weather
Solar Radiations Specially.
Or. Abbots special field has been
the study Of solar radiation, upon which
the life Of the world depends. The
amount Of heat radiated by the sun
varies slightly from day to day DR..
Abbot in the past has designed ex-
tremely delicate instruments for detect
ing the amounts Of this variation. There
1-aF - - II l..
intricate relationship between this vari-
ability and the worlds weather.
The daily observations taken at the
Smithsonian's three solar observatories
in different parts Of the world are aver
aged each month, and the monthly
are plotted. The result, over
q period Of years, is an irregular curve
which rises and falls on the plotting
paper like the relief map Of a noun
famous country. The problem has been
TO find whether there is any sequence
of variations. Does the heat of the sun.
for example, vary from high to low in
eight-month intervals? The curve shows
clearly that It does. The eight-month
cycles are so conspicuous that they OBJ
scure any other periodicities that may
be present.
DR.. Abbot suspected, however that
eAAAo FASA4t-IAOilLAl 1OQ WAS IlOL LQe
only one. He worked 1t out by an ex-
tremely laborious mathematical process
and discovered four other periods of |
regular varistion-intervals respective |
", Of 81, IS, Is and IL months. II was |
while engaged on this work that the |
dea OF the machine came to the sfnith- |
Sontan secretary. So ne devised the |
brass brain" which would do the !
same thing. AS finally realized, the de- |
vice is quite simple IN comparison with !
most mathematical machines 1t can
be operated by person without train
Ing IN mathematics.
Machine ErrorIess.
It is not a rapid calculator. Dr.. Alb
bot said today ne is not sure that it
will be possible to work out the peri
odicities any faster with this mechan-
ism than with pencil and paper. The
machine, however, is not subject to
human errors, and in work of such ex-
sctneSs a slight mistake might throw
the investigator far of.
Measurements of solar radiation. II
was shown by another exhibit, have
reached such an extreme accuracy that,
In the face Of varying conditions in the
atmosphere, there is a difference of only
about one-tenth Of l per cent in the !
curves based on observations in the |
Southwest, in Chile and in South Africa
What is perhaps the worlds most
measured stalk Of wheat was shown the
regents. 1t is healthy stalk grown in
q glass tube without any soil, its roots
being immersed in liquid chemical So
luton the constituents of which are
exactly known. Every bit of light, heat
and humidity the stalk has experienced
from the first has been exactly meas
ureu. Every bit Of carbon dioxide it alb
serbs Is measured automatically In
this way II is hoped TO learn the exact
coalitions under which wheat grows
An interesting historical exhibit was
the original model Of the sewing ma
chine made by Elias Howe, jr., in l845.
a year before he obtained his patent.
II has beer deposited with the Smith
sor1ian by his niece, Mrs. Jennie Teel.
Among the exhibits was a prehistoric
cradle obtained from a Texas cave con-
tanning artifacts of hitherto unknown
culture by p. M. Settler of the Smith
sopian staff
The following members of the Board
OF. Regents attended the meeting yes
tetdsy: Chief Justice Charles Evans
Hughes, Senators Reed Smoot. Joseph
T. Robinson and Claude A. Swanson:
Representatives Albert johnson and
Robert Luce, r. Walton Moore, Fred
eriek A. Delano and DR.. j. c. Merriam.
FOR SENATE