Evening star., 1939-04-22
Of Stors, Men
And Atoms
Notebook Of Science Progress
In Field. Laboratory
And Study
BIZ Thomas r. Henri.

The newly discovered mesotron, ele-
mentary particle with about 200 times
the mass of an electron and which is
responsible for the most penetrating ra-
diation of cosmic rays, probably has an
average life of only about millionth Of
a second, according to evidence sum-
married by DR.. Earl K. Darrow Of the
Bell Telephone Co. in the current issue
of the Scientific Monthly.
The present picture, he said is that Of
a heavily charged particle, probably
formed in some way in the upper limits
of the atmosphere, which very rapidly
emits positive or negative electron.
The result is that it looses its charge
and can no longer be detected. The
short life of the particle, he explains,
can be postulated by counting the num-
bers striking spot on the earth's sur
face at different angles from the vertical.
Those coming straight downward cover
the shortest path. The path increases
IN length as the angle is increased.
Hence it may be deduced that, if the
period between the formation of the
mesotron and it's decadence into an un-
detachable neutral particle is very brief,
then the number received at the earths
surface will vary according to the angle
of incidence.
This is precisely what is observed in
numerous experiments, DR.. Darrow says.
The mesotron is moving at approximately
the speed Of light, so there must be a
very brief lifetime, indeed, If any differ
ence is to be noted.
Another line of evidence he sums up
as follows: Let us compare the effect OF
the obliquely traversed atmosphere with
that OF sheet of lead in cutting down
the number of particles arriving at the
apparatus One must make a guess as
to the thickness of lead which would be
required to produce falling of of the
number of particles equivalent to that
observed in the atmosphere If the falling
on were due to the actual stopping of
mesotrons in air and lead respectively
and the impermanence of the mesotron
did not enter in at all.
1T is commonly conjectured that the
equivalent thickness of lead and air
would stand to one another inversely as
the densities of these materials When,
however, the effects of such equivalent
thlcknesses are compared, 1t is found
that the falling of beyond the lead is
decidedly less than that beyond the air.
NOW the mesotrons take very much less
time for traversing the sheet of lead
than for traversing the atmosphere and
the annpO 1v ie rtoti
assuming that few OF them perish in the
lead. many in the long journey through
the atmosphere
Plants and insects unknown elsewhere
IN the world are to be found on Santa
Catalina Island, favorite resort of Cali
fornla vacationists, according to a report
just published in the Scientific Monthly
by Dr. T. D. A. Cockerell of the Uniyer-
sity of Colorado.
IL Is one OF group Of eight islands OH
the California coast, remnant of a large
land formation which probably was
Joined to the mainland in Miocene times.
between about 100000 and $1,000 900
years ago.
Among the unique plants is a shrub
with beautiful white flowers which face
downward and are suggestive of apple
blossoms The fruits are very peculiar.
with fingerlike follicles rather suggest
Ing peony. Locally this is called the
Wild APPLE although there is no rela-
tonshlp whatsoever to the true apple.
With one other species found in the
deserts of the Southwest it represents a
distinct family Of plants.
1t is unquestionably of great ANTIQUITY.
Dr. Cockerell says, and at one time prob
ABLY occupied much larger territory.
No fossil remains have yet been found in
other regions.
Another remarkable plant confined en-
tlrely to this little group of islands is a
tree about 30 feet high which grows in
steep-Walled gulches and in June is cov-
cred with beautiful white flowers. Lo-
cally 1t is known as 'ironwood," which
Dr. Cockerell calls an altogether mis-
leading name.
Another curiosity in the flora of the
lsiands is the f1gwort, a tall plant which
pears long spikes of dark -colored flowers.
ltsls visited by numerous bees of a dis
tlnct species, gray insects which fy
rapidly from flower to flower.
BESIDES several varieties of insects the
lslano mas three mammals found no.
Where else, small fox and two varieties
OF mice. There is also a race of Quail
round nowhere else-about per cent
larger and darker in color than It's near
est mainland relative.
Dr. Cockerell made special study of
tne beetles. He found about 80 species.
belonging to three families, to be con-
nned to Santa Catalina Island. Several
OF these are large, black ground beetles,
unable to fly. While all the plants, NAM
mas and birds of the islands probably
nave been recorded, DR.. Cockerell saws,
1T is likely that several hundred yarie-
ties OF insects still have not been COL
lected and probably will yield many new
->>S cav"