The New York herald., 1922-11-05


atmospheric electricity has a shorter
non-lunar one Of 1898 days. Arrhenius
demonstrated the same double periodic
ity for epilepsy. but found it to be ao-
sent for bronchitis and mortality.
Popular beliefs IN a favorable inhu-
ence of the moon on plant growth are
both worldwide and ancient, although
most of them are probably on a par
with the superstition that a waxing
moon increases, waning moon de-
creases. any process such. for instance. as
tho acquisition of wealth. Seneca, Galen
and other classical authors speak Of the
moon az Fastening the maturation of
fruits. Athenio is more precise, writing
that "cucumbers in gardens grow at
full moon, showing a visible develop
ment, and so do sea urchins." This quo
tation Is OF special interest in relation
to a common belief of the modern Egyp-
tians that melons, marrows and other
fruits OF the natural order Cucurbitace@
grow Nost rapidly on moonlit nights.
An Investigation of the rate OF growth
of these fruits, extended over three
months, has shown me. however. that
there is no basis at all for this belief.
As tho lunar influence is supposed to
show itself especially in these cucurbi
taceous fruits. It may safely be assumed
to be absent In all fruits.
Nevertheless. since the popular belief
IN the existence Of lunar cycle in sea
urchins has turned out to be so unex-
pectedly true. one is bound to ask
whether any other of the superstitions
about plants too are based on fact. 1t
is conceivable, for instance, that moon
light may have a photosynthetic effect.
Kofoid found q lunar periodicity in the
freQuencies of plankton organisms in
the Illinois River. Allen discovered the
same thing In the San Joaquin River,
California The maximum frequency
If alga occurred at full moon, that of
crustacea a little later While the
crustacean presumably follows the algal
maximum because the animals feed on
the plants, Kofoid attributes the algal
maximum occurring about full moon to
a photosynthetic effect of moonlight
He supports this hypothesis by reference
to experiments of Knaute, who states
that he found the oxygen content of
water containing Euglena to be higher
in moonlight than in darkness, which
means that the moonlight causes photo.
synthesis. Knaute says that the photo
synthetic effect Iof moonlight is to that
of sunlight as 2!9. This is a surprisingly
high ratio. since the light of the sun Is
about 100000 times that of the full
moon.
There are two demonstrated effects of
moonlight upon plants. Firstly. Musset
showed that n number OF Towering
plants are positively phototropic to
moonlight The stems bend toward the
moon and during the course of the night
move round to follow its path Sec
ondly, Loftfield states that at night
stomata open as a result OF illumination
by moonlight The consequent periodic
opportunity for increased Transportation
and respiration might conceivably cause
other rhythmic changes in the plant,
with a lunar period.
In conclusion. two cases of lunar
effects on the migration of fish must be
mentioned. The first concerns herring
and is of peculiar interest, since the
rather intricate casual connection has
been elucidated The work was done
by Peterson. Herring are not found
in the Baltic because the water is not
sufficiently salt. They migrate into the
Kattegat, however, with an undercurrent
Of salter water which exists beneath the
less dense surface layers. This under
current is oscillatory and the movement
shows itself by changes in the level of
the deep salter water.
The crests of the submarine waves
occur at intervals OF about thirteen and
a half days, that is. the undulatory
movement has the tropical lunar period
Of twenty-seven days and depends on
the moons declination. That the her
ring move with the salt water is shown
by tie fact that the dates of the great
est herring catches are those on which
the crests Of tho waves of salter water
occur.
But this is not all. During the last
century and a half the years Of maximum
and minimum herring fisheries are found
to coincide with the years of maximum
and minimum declination Of the moon.
which are 9.3 years apart 1t may be
presumed that the fishery has this period
OF 1876 years because of a variation of
odAbeN Win lne same
period. The herring fishery has also
longer period which can be traced back
1000 years. The maxima are III years
apart. This is the greater~ sunspot
period. but since s multiplied by 1876
equals 111.6 the moons decllnation may
again be the real cause.
The second case of lunar effect on
the migration of fish is the following
DIR. Johann Schmidt informs me that
Danish eel fishermen. who catch silver
cells with nets in the shallow water as
they migrate out of the Baltic in the
autumn, expect to obtain better catches
in the interlunar periods than when there
is moonlight. In Egypt too the eel fish
ermen look forward to the best catches
when there is no moon. G. w. Paget,
Egyptian Government Director OF Fish
cries. suggests In explanation OF this
direct effect OF the light OF the moon In
\ topping the migration of the cells. bas-
nE his opinion on successful experiments
carried out in Denmark on artifcially
stopping eel migratlons with acetylene
amps The Italians too light fires when
they want 20 interrupt a migration In