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scientificamerican.com/magazine/saJunEScientific American,Vol. 226, No. 6; June 1972187219221972
Neutrino Trap
“It is believed that
the sun’s radiant energy originates
with thermonuclear reactions deep
in the interior. One product should
be a flood of neutrinos: massless,
uncharged particles that interact
so little with other particles that
solid bodies such as the earth are
virtually transparent to them. Ray-
mond Davis, Jr., of the Brookhaven
National Laboratory has devised
a detector to test the theory. It is
buried a mile under solid rock
in the Homestake Gold Mine in
Lead, S.D., a huge tank containing
100,000 gallons of the dry-cleaning
solvent tetrachloroethylene, 85 per-
cent chlorine. When a neutrino is
absorbed by an atom of chlorine,
an atom of the radioactive isotope
argon 37 is formed. At intervals of
about 100 days the tank is swept
with helium gas to remove the
argon 37. Theory predicts that neu-
trinos are produced at such a rate
that Davis’s detector should cap-
ture two neutrinos per day. Results
over the past two years show that
the capture rate is less than 0.2
neutrino per day. Explanations
of the discrepancy are varied, but
none is very satisfactory. The prob-
lem is certain to receive intense
study in the near future.”1922
Guatemala
in Two Acres
“The republic of Guatemala, to
make it easy for visiting capitalists
to decide on proposed investments,
has built what seems by all odds
the most extraordinary relief map
in the world. This map is two acres
in extent, and shows every contour,
every town and every stream or
lake in Guatemala and the neigh-
boring territory of British Hondu-
ras. The giant topographical map
is of concrete, assembled in sec-
tions. Almost two years were spent
making the molds, and checking
them up. The ultimate cost was
$100,000, and another like sum
was spent in gathering the data
on which the map is based. The
big map is located in the hippo-
drome, or racetrack, at Guatemala
City, and it has passed through
two earthquakes without harm.”
the map still exists, albeit as
a tourist attraction.We Ought to Be
in Pictures
“Scientific American has entered
the motion picture field, as pro-
ducers of Scientific American films,
in collaboration with the Coronet
Films Corporation of Providence,
R.I. The films, which will appear
once a month, will be shown in
theaters throughout the country.
Subjects will be taken from our
columns and transplanted to
the screen. We also have inaugu-
rated a special radio-phone broad-
casting talk in order that we might
report and comment on the scien-
tific news of the day. We are using
the WJZ station of the Radio Cor-
poration-Westinghouse organiza-
tions, located at Newark, N.J., cov-
ering a range of several hundred
miles. In the very near future weshall make arrangements to cover
more or less the entire country.”1872
Solar System
Causes Cholera
“B. G. Jenkins recently read, before
the Historical Society of London,
a remarkable paper, in which he
maintained that cholera is inti-
mately connected with [the cycle
of sun spots, which has a period
of 11.11 years]. He said, ‘Cholera
epidemics have, I believe, a period
equal to a period and a half of sun
spots. The date 1816.66 was shortly
before the great Indian outbreak;
another period and a half gives
1833.33, a year in which there was
a maximum of cholera; another,
1849.99, that is, 1850, a year having
a maximum of cholera; another,
1866.66, a year having a maximum
of cholera; in 1883.33 there will be
a maximum. I am not prepared to
say that sun spots originate chol-
era; for they may both be the
effects of some other cause. My
own opinion is that planets, in
coming to and going from peri-
helion—more especially about the
time of the equinoxes—produce a
violent action upon the sun [pro-
ducing] a maximum of sun spots,
and in connection with it a maxi-
mum of cholera on the earth.’ ”Sanitary Lead Pipes
“Several citizens of Sacramento,
Calif., having been poisoned by
the use of what is known as the
‘sanitary composite’ water pipe.
The Board of Health has ordered
its use to be discontinued. Water
flowing through this pipe was
found, on chemical analysis, to
contain lead and arsenic. The pipe
in question is believed to be com-
posed of a species of brass.”19721972: The map shows the “range of submarine-launched ballistic missiles that could hit strategically
important targets in the U.S.S.R., assumed to include population centers and industrial complexes,
within 200 miles of the border ( gray areas ). Contours are concentric with the border. The solid ( blue )
contour shows the range of the Polaris A-3 and Poseidon C-3 missiles (2,500 nautical miles). The
two inner broken contours show the ranges of older missiles. The two outer broken contours show
the estimated ranges of the Navy’s proposed undersea long-range missiles (4,500 and 6,000 nautical
miles). Black dots denote home ports and forward bases of the U.S. missile-submarine fleet.”