Evening star., 1938-08-09
OF STARS,
MEN AND ATOMS
Notebook of Science Progress
in Field, Laboratory
and Study.
By THOMAS r. HENRY.

by 7HOMAS X. HENRY.
There will be no weather supersti-
tions left If DR.. William j. Humphreys,
veteran meteorologist of the United
States Weather Bureau, lives long
enough.
For nearly half century he has pro-
-vided physical explanations, one after
another. for ancient bits of weather folk
lore His latest attack, just published
in the Weather Bureaus monthly re-
view, is on mysterious springs that flow
only at night, or only during droughts,
or only after the first heavy frost.
Paradoxical as these seem. DR.. Hum
phreys says, the explanations are simple
enough when they are considered as
purely physical phenomena.
Some springs flow only at night. These
usually are in the woods. This is be-
cause, DR.. Humphries explains, the
ground water has two outlets. one by
seepage and veinlike drainage to springs,
and the other through evaporation from
the myriads of leaves overhead. Evapo-
ration is least at night. Hence seepage
is greatest.
Much the same explanation applies to
those mysterious springs which may
remain dry or very weak all summer and
start good flow with the first heavy
frost. The frost kills the leaves. Evapo-
ration stops and the water in the soil
must find another outlet.
There are springs. especially in lime
stone regions, which will remain dry
most of the time. but suddenly start to
flow at the approach of heavy rain,
but hours before any rain actually has
barometer
harbingers Of rain.
Sometimes" says DR.. Humphreys,
Every little rain falls and then the
fluctuations of this kind are distinctly
drought phenomena. They do not take
place where rains are frequent enough
to maintain good supply of ground
water. Their explanation is simple.
The channel in such spring leads to
cavity which, during a prolonged dry
spell, when the seepage into it is be-
coming less and less, gradually empties.
Meanwhile air slowly filters in until
the water pressure at the reservoir out
let. below the surface, is no longer suf-
ficient to force an outflow
If the pressure Of the open air should
be lowered while that Of the rather
closely entrapped air in the half-emptied
underground reservoir is unchanged. wa
ter is forced out from the place of the
greater to that of the lesser pressure
that is, from the half-filled cavity to the
open spring. Now a marked decrease Of
atmospheric pressure is just what hap
pens at the approach Of general rain.
often beginning hours ahead OF the pre-
cipitation. Thus it causes certain springs
to run again in the midst of drought
this mysterious flow prophetic Of rain.
Here and there occurs a spring that
flows a while and stops a while, day in
and day out, year in and year out. Folks
invent explanations for such spring
as fanciful as medieval gnome or hob
goblin. There are two kinds of these in
termittent springs-the cold water kind,
which every physicist understands, and
the hot water kind that not even the
chemist understands in every particular.
The fo-, of the cold intermittent spring
is just the emptying of an underground.
air-connected water cavity by natural
syphon tube. Obviously when the reser-
voir is emptied to the level of the syphon
intake the flow ceases. The spring goes
dry and stays dry until the reservoir fills
in the tube. whereupon the flow and the
stop occur again as before, over and over
without end.
The hot-water type. confined to lime
stone regions, commonly is called
geyser, even when it just mildly over
flows. It's intermittent spurts appear to
be the repeated blowing out by steam
of an underground reservoir that as
often fills up again. Where all this wa
ter comes from and how it gets into the
steam chamber are not known to the
complete satisfaction of every one. 1t is
easy enough to make laboratory geyser
that works perfectly, but that does not
prove that Nature made hers on the
same plan"
The skeleton OF a titanosaur, most
terrible OF the flesh-eating dinosaurs,
now is being pieced together by Smith
sonian Institution paleontologists.
This was the dominant creature over
most Of the earth about 100000, 900 years
ago. 1t has 50-foot tail, height of
approximately IS feet, teeth from to
inches long, weighed between IS and 20
tons, and was ferocious flesh eater.
The fossil bones were obtained in
Utah last summer by Dr. Charles w.
Gilmore, curator Of vertebrate paleon-
tology. The find attracted some atten-
ton at the time because it came from
rock strata laid down several million
years after the great flesh-eating dino
saurs hitherto had been considered ex-
tinct.
Other finds of fossils Of the same
group, Dr. Gilmore says, have been re-
ported from India. Madagascar, France
and South America While dinosaurs
were almost world wide in their distri-
button, most families show considerable
variation from place to place. All the
titanosaurs. however, seem to show a
stabilized form in which it is difficult
to find even species differences.
The upper cretaceous age of geological
time must have been a nightmare period
in earth's history with these blood
hungry, almost brainless monsters mas
tiers of creation to an extent hardly ex-
ceeded by any other species before or
since.