Evening star., 1930-12-12
PLUTO AND EARTH
NEARLY SAME SIZE
Carnegie Institution Exhibits
Recent Scientific Findings
in PaIeOntoIogy.

The planet, Pluto, ninth member of
the solar system discovered last year
from the Lowell Observatory, is of ap-
proximately the same size as the earth.
The first determinations of the mass
were announced today by the Carnegie
Institution of Washington. They were
determined by DR.. Seth B. Nicholson
and Nicholas u. Mayell of the Mount
Wilson Observatory
The orbit of Neptune which. If the
planet were subject to no attraction
from other bodies. would be a perfect
eclipse shows certain slight Irregular
itiss due to the new planet lying beyond
1t in space. The Carnegie investigators
found that the observed motion of Nep-
tune would be caused by body of about
the mass of the earth, value subject
10 an uncertainty of about 25 per cent.
photographs of Pluto and drawings
showing the effect of this planet on the
motion of Neptune will be on display
1t the Carnegie Institution tomorrow
and Sunday, both afternoon and
evening.
Ancient Land Bridge Studied.
1t also was announced today that
Carnegie scientists have established the
existence of an ancient land bridge be-
tween North America and Asia by way
OF ST. Lawrence Island in the Bering
Strait. This has long been suspected
because of the similarity and plant and
animal life on the two continents.
The now barren island, about 40
miles from the Kamchatka peninsula
and 100 miles from the coast of Alaska,
once was covered by a great redwood
forest, similar to that now in California.
The ancient redwoodS were Identified bv
Or. Ralph w. Chaney, Carnegie paleo-
botanist, in fossils brought OF the
island this summer by DR.. Henry r
Collins of the Smithsonian Institution.
1t is probable according to DR.. Cha
ney, that 50,000,000 years ago the red
wood forest was continuous from Cali
tornia to Kamchatka and that st. Law
renee Island was part of an uubroken
highway over which the first human
settlers OF North America may have
passed. together with many animals.
Earth's History Recorded.
The institution also is showing this
year, for the first time, some of the
earliest pages of the earths history as
recorded on rocks. These date from the
pre-Cambrian period, probably a thou
sand million years ago, and have been
nttle altered by pressure and heat
through the ages. They show tiny pits
made by raindrops in the sediment
from which they were formed, as well
as cracks made by the sun. There is
considerable evidence of low orders of
plant life, including seaweedS. There
IS no trace, however. of even the lowest
forms of animal life which might have
been expected to have been present in
Cne beginning and to have fed on the
abundant plants
This does not necessarily mean that
there were no animals. it is explained,
but that such creatures as existed then
had no shells, scales or skeletons which
would make an impression in the soft
sediment. Also, it is pointed out, they
may have been too small to have left
recognizable traces or may have been
so different from later animals that
paleontologists do not know what to
look for.
The contested issue of the age of the
human race in North America is re-
yived by exhibits obtained this year
from a cave in Nevada, where man.
made implements were found in close
association with bones of the ground
sloth and other extinct animals.
VIII See Life Process.
Visitors to the exhibit this year will
be able to see for the first time one of
the fundamental life processes. Each
living cell is a battery sending out elec-
trlc currents, but most cells are micro
scopic in size, so that it is impossible
10 observe what happens.
For this exhibit use is made of the
cells Of the water plant valonia, which
Is about the size of a hens egg and
consists of tough papery bag, the cell !,
wall, lnclosing thin continuous film of
protoplasm which surrounds the sap" |
solution Of salts very different in COM |
position from the surrounding sea water. ,
such cells can be handled easily in an |
electric circuit.