Scientific American Supplement, No. 841, February 13, 1892 online

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and these grew better and were larger than those exposed to its direct
rays. The average weight of eight plants in full light was 49.6
grains, as opposed to an average of six plants in the shade of 93.8
grains. Radishes were strongly attracted to the light and moved toward
it during the night. During the day they straightened up, but moved
again toward the light at night. The plants nearest the lamp made a
poor growth and were nearly dead at the end of six weeks. Averaging
the weight of plant, of top and of tuber, it was found that those
grown in the dark were heavier in every instance than those grown in
the light; and the percentage of marketable tubers from the
light-grown plants was twenty-seven, as opposed to seventy-eight in
the dark. Chemical analyses showed the plants in the light to be more
mature than those in the dark, although they were much smaller. Dwarf
peas showed the same facts, those in full light being smaller than
those in the dark. The former bloomed a week earlier than the latter,
but the production of seed was less, being only about four-sevenths as

Further experiments were made by excluding the sun during the day and
exposing the plants to the diffused electric light only. In all cases,
with radishes, lettuce, peas, corn, and potatoes, the plants died in
about four weeks. Only a little starch and no chlorophyl was found in
the plants deprived of sunlight and only receiving the electric light.
Thus the experiments with a naked light showed conclusively that
"within range of an ordinary forcing house the naked arc light running
continuously through the night is injurious to some plants." In no
case did it prove profitable.

Experiments with the light inclosed in a white globe and running all
night were different in their results. The effect was much less
marked. Lettuce was decidedly better in the light house; radishes were
thrifty but did not produce as much as in the dark house. A third
series of experiments with the naked light running a part of the night
only were also made. Radishes, peas, lettuce, and many flowers were
experimented upon. The lettuce was greatly benefited by the light.
"Three weeks after transplanting (Feb. 5)," we are told, "both
varieties in the lighthouse were fully 50 per cent. in advance of
those in the dark house in size, and the color and other characters of
the plants were fully as good. The plants had received at this time
70½ hours of electric light. Just a month later the first heads were
sold from the light house, but it was six weeks later when the first
heads were sold from the dark house. In other words, the electric
light plants were two weeks ahead of the others. This gain had been
purchased by 161¾ hours of electric light, worth at current prices of
street lighting about $7."

This experiment was repeated with the same results. In the second
experiment the plants receiving eighty-four hours of electric light,
costing $3.50, were ready for market ten days before the plants in the
dark house. The influence of the light upon color of flowers was
variable. With tulips the colors of the lighted plants were deeper and
richer than the others, but they faded after four or five days.
Verbenas were injured in every case, being of shorter growth and
losing their flowers sooner than those in the dark house. "Scarlet,
dark red, blue and pink flowers within three feet of the light soon
turned to a grayish white." Chinese primulas seven feet from the light
were unaffected, but those four feet away were changed. Lilac colors
were bleached to pure white when the light struck them fairly. An
elaborate series of tables of the effect of the light is given in the
paper. The author believes it possible that the electric light may be
used some day to pecuniary advantage in floricultural establishments.

These experiments naturally open up many questions. Those which will
be of most importance to the practical man will be such as relate to
the benefits to be derived from the use of the electric light. That
electricity has a great effect upon vegetation can no longer be
denied. What remains now is to ascertain how to use the force with the
most economy and to the best advantage. If by its use early vegetables
will be made earlier, bright flowers be made brighter, it will be a
question of only a short time before it will come into general use. To
the student of plant physiology there are also many questions of
interest, but into these it is not the intention to enter. Prof.
Bailey's general conclusions are, in part, as follows: "There are a
few points which are clear: the electric light promotes assimilation,
it often hastens growth and maturity, it is capable of producing
natural flavors and colors in fruits, it often intensifies colors of
flowers and sometimes increases the production of flowers. The
experiments show that periods of darkness are not necessary to the
growth and development of plants. There is every reason, therefore, to
suppose that the electric light can be profitably used in the growing
of plants. It is only necessary to overcome the difficulties, the
chief of which are the injurious influences upon plants near the
light, the too rapid hastening to maturity in some species, and in
short the whole series of practical adjustments of conditions to
individual circumstances. Thus far, to be sure, we have learned more
of the injurious effects than of the beneficial ones, but this only
means that we are acquiring definite facts concerning the whole
influence of electric light upon vegetation; and in some cases,
notably in our lettuce tests, the light has already been found to be a
useful adjunct to forcing establishments.... It is highly probable
that there are certain times in the life of the plant when the
electric light will prove to be particularly helpful. Many experiments
show that injury follows its use at that critical time when the
planetlet is losing its support from the seed and is beginning to
shift for itself, and other experiments show that good results follow
from its later use.... On the whole, I am inclined toward Siemens'
view that there is a future for electro-horticulture."

Washington, Jan. 20, 1892.

* * * * *


It is well known that currents of electricity exist in the atmosphere.
Clouds are charged and discharged. There is a constant change of
electricity from earth to air and from air to earth, the latter being
the great reservoir for all electricity. Hills, mountain peaks, trees,
high chimneys, spires, in fact all points elevated above the earth's
surface assist greatly in charging and discharging the atmosphere.
Again, if two iron rods are driven into the earth and connected by a
copper wire with an electrometer in the circuit, the instrument is
almost immediately affected, showing that currents of electricity are
running through the ground. Now, what is the function of these
atmospheric and ground electric currents? Many scientists are agreed
that certain forms of precipitation are due to electrical action; but
my observations have led me to believe conclusively that electricity
is a potent factor in the economy of nature, and has more to do with
the growth and development of plants than has hitherto been known.
Davy succeeded in the decomposition of the alkalies, potash and soda,
by means of electric currents. In our laboratories, water and ternary
compounds are rapidly decomposed by the battery, and we may reasonably
suppose that that which is effected in our laboratories by artificial
means takes place in the great laboratory of nature on a grander and
more extended scale.

Plant food is carried throughout the plant by means of the flow of
sap; these currents circulate through all the rootlets and center, as
it were, in the stalk, carrying their tiny burdens of various elements
and depositing them in their proper places. That this phenomenon of
circulation is due to electricity cannot be doubted. Most plants grow
more rapidly during the night than in the day. May not the following
be a reason for this?

We have already mentioned how electric currents pass from air to earth
and _vice versa_; at night the plant is generally covered with dew and
the plant itself becomes a good conductor, and, consequently, currents
of electricity pass to each through this medium, and during the
passage convert soil elements into plant food and stimulate the upward
currents to gather up the dissolved elements and carry them to their
proper places.

From the time electricity became a science, much research has been
made to determine its effect, if any, upon plant growth. The earlier
investigations gave in many cases contradictory results. Whether this
was due to a lack of knowledge of the science on the part of the one
performing the experiments, or some defect in the technical
applications, we are not prepared to say; but this we do know, that
such men as Jolabert, Nollet, Mainbray and other eminent physicists
affirmed that electricity favored the germination of seeds and
accelerated the growth of plants; while, on the other hand,
Ingenhouse, Sylvestre and other savants denied the existence of this
electric influence. The heated controversies and animated discussions
attending the opposing theories stimulated more careful and thorough
investigations, which establish beyond a doubt that electricity has a
beneficial effect on vegetation. Sir Humphry Davy, Humboldt, Wollaston
and Becquerel occupied themselves with the theoretical side of the
question; but it was not till after 1845 that practical electroculture
was undertaken. Williamson suggested the use of gigantic electrostatic
machines, but the attempts were fruitless. The methods most generally
adopted in experiments consisted of two metallic plates - one of copper
and one of zinc - placed in the soil and connected by a wire. Sheppard
employed the method in England in 1846 and Forster used the same in
Scotland. In the year 1847 Hubeck in Germany surrounded a field with a
network of wires. Sheppard's experiments showed that electricity
increased the return from root crops, while grass perished near the
electrodes, and plants developed without the use of electricity were
inferior to those grown under its influence. Hubeck came to the
conclusion that seeds germinated more rapidly and buckwheat gave
larger returns; in all other cases the electric current produced no
result. Professor Fife in England and Otto von Ende in Germany carried
on experiments at the same time, but with negative results, and these
scientists advised the complete abandonment of applying electricity to
agriculture. After some years had elapsed Fichtner began a series of
experiments in the same direction. He employed a battery, the two
wires of which were placed in the soil parallel to each other. Between
the wires were planted peas, grass and barley, and in every case the
crop showed an increase of from thirteen to twenty-seven per cent.
when compared with ordinary methods of cultivation.

Fischer, of Waldheim, believing atmospheric electricity to aid much in
the growth and development of plants, made the following tests:

He placed metallic supports to the number of about sixty around each
hectare (2.47 acres) of loam; these supports were provided at their
summits with electrical accumulators in the form of crowns surmounted
with teeth. These collectors were united by metallic connection. The
result of this culture applied to cereals was to increase the crop by

The following experiment was also tried: Metallic plates sixty-five
centimeters by forty centimeters were placed in the soil. These plates
were alternately of zinc and copper and placed about thirty meters
apart, connected two and two, by a wire. The result was to increase
from twofold to fourfold the production of certain garden plants. Mr.
Fischer says that it is evidently proved that electricity aids in the
more complete breaking up of the soil constituents. Finally he says
that plants thus treated mature more quickly, are almost always
perfectly healthy, and are not affected with fungoid growth.

Later, N. Specnew, inspired by the results arrived at by his
predecessors, was led to investigate the influence of electricity on
plants in every stage of their development; the results of his
experiments were most satisfactory and of practical interest. He began
by submitting different seeds to the action of an electric current,
and found that their development was rendered more rapid and complete.
He experimented with the seeds of haricot beans, sunflowers, winter
and spring rye. Two lots, of twelve groups of one hundred and twenty
seeds each, were plunged into water until they swelled, and while wet
the seeds were introduced into long glass cylinders, open at both
ends. Copper disks were pressed against the seeds, the disks were
connected with the poles of an induction coil, the current was kept on
for one or two minutes and immediately afterward the seeds were sown.
The temperature was kept from 45° to 50° Fahrenheit, and the
experiments repeated four times. The following table shows the

Peas. Beans. Barley. Sunflowers.
Days. Days. Days. Days.
Electrified seeds developed in 2.5 3 2 8.5
Non-electrified seeds developed in 4 6 5 15

It was also observed that the plants coming from electrified seeds
were better developed, their leaves were much larger and their color
brighter than in those plants growing from non-electrified seeds. The
current did not affect the yield.

At the Botanical Gardens at Kew, the following experiment was tried:

Large plates of zinc and copper (0.445 meter and 0.712 meter) were
placed in the soil and connected by wires, so arranged that the
current passed through the ground; the arrangement was really a
battery of (zinc | earth | copper). This method was applied to pot
herbs and flowering plants and also to the growing of garden produce;
in the latter case the result was a large crop and the vegetables
grown were of enormous size.

Extensive experiments in electroculture were also made at Pskov,
Russia. Plots of earth were sown to rye, corn, oats, barley, peas,
clover and flax; around these respective plots were placed insulating
rods, on the top of which were crown-shaped collectors - the latter
connected by means of wires. Atmospheric electricity was thus
collected above the seeds, and the latter matured in a highly
electrified atmosphere; the plots were submitted to identical
conditions and the experiments were carried on for five years. The
results showed a considerable increase in the yield of seed and straw,
the ripening was more rapid and the barley ripened nearly two weeks
earlier with electroculture. Potatoes grown by the latter method were
seldom diseased, only to 5 per cent., against 10 to 40 per cent. by
ordinary culture.

Grandeau, at the School of Forestry at Nancy, found by experiment that
the electrical tension always existing between the upper air and soil
stimulated growth. He found plants protected from the influence were
less vigorous than those subject to it.

Macagno, also believing that the passage of electricity from air
through the vine to earth would stimulate growth, selected a certain
number of vines, all of the same variety and all in the same condition
of health and development. Sixteen vines were submitted to experiment
and sixteen were left to natural influences. In the ends of the vines
under treatment, pointed platinum wires were inserted, to which were
attached copper wires, leading to the tops of tall poles near the
vines; at the base of these same vines other platinum wires were
inserted and connected by copper wires with the soil. At the close of
the experiment, which began April 15, and lasted till September 16,
the wood, leaves and fruit of both sets of vines were submitted to
careful analysis with the following results:

Without conductor. With conductor.

Moisture per cent. 78.21 79.84
Sugar. 16.86 18.41
Tartaric acid. 0.880 0.791
Bitartrate of potash. 0.180 0.186

Thus we see that the percentage of moisture and sugar is greater and
the undesirable acid lower in those vines subject to electrical
influences than in those left to natural conditions. There are also
experiments which prove the beneficial effects of electricity on vines
attacked by phylloxera.

The following experiments were made at this station: Several plots
were prepared in the greenhouse, all of which had the same kind of
soil and were subjected to like influences and conditions. Frames in
the form of a parallelogram, about three feet by two feet, were put
together; across the narrow way were run copper wires in series of
from four to nine strands, each series separated by a space about four
inches wide, and the strands by a space of one-half inch. These frames
were buried in the soil of the plot at a little depth, so that the
roots of the garden plants set would come in contact with the wires,
the supposition being that the currents of electricity passing along
the wires would decompose into its constituents the plant food in the
vicinity of the roots and more readily prepare it for the plants. Two
electric gardens were thus prepared and each furnished with two common
battery cells, so arranged as to allow continuous currents to pass
through each series of wires. Near each electric garden was a plot
prepared in the same manner, save the electrical apparatus. We will
call the two gardens A and B.

The place chosen for the experiments was in a part of the greenhouse
which is given up largely to the raising of lettuce, and the gardens
were located where much trouble from mildew had been experienced. The
reason for this choice of location was to notice, if any, the effect
of electricity upon mildew, this disease being, as it is well known, a
source of much trouble to those who desire to grow early lettuce. The
soil was carefully prepared, the material taken from a pile of loam
commonly used in the plant house.

Garden A was located where mildew had been the most detrimental; the
experiments began the first of January and closed the first of April.
For the garden, fifteen lettuce plants of the head variety were
selected, all of the same size and of the same degree of vitality, as
nearly as could be determined; the plants were set directly over the
wires, so that the roots were in contact with the latter; the plants
were well watered and cared for as in ordinary culture, and the fluid
in the battery cells was renewed from time to time, that the current
of electricity might not become too feeble. At the close of the
experiments the following results were noted:

Five plants died from mildew, the others were well developed and the
heads large. The largest heads were over the greatest number of wires
and nearest the electrodes. It was further noticed that the healthiest
and largest plants, as soon as the current became feeble or ceased
altogether, began to be affected with mildew. On examining the roots
of the plants it was found that they had grown about the wires as if
there they found the greatest amount of nourishment; the roots were
healthy and in no way appeared to have been injured by the current,
but, rather, much benefited by the electrical influences.

Beside garden A was prepared another plot of the same dimensions,
having the same kind of soil and treated in like manner as the first,
but the electrical apparatus and wires were wanting. At the close of
the experiments only three plants had partially developed, and two of
these were nearly destroyed by mildew - one only was free from the
disease. The results, therefore, show that the healthiest and largest
plants grew in the electric plot.

In the second experiment, which we called B, twenty plants of the same
variety of lettuce and of equal size were taken. The treatment given
was the same as the plants in plot A received. Five plants only
remained unaffected with mildew; seven died from the disease when they
were half grown; the rest were quite well developed, but at the last
part of the experiment began to be affected. Several heads were large,
the largest being over the greatest number of wires and nearest the
electrodes. Examination of the roots disclosed the same phenomena as
in A.

Near plot B were also set twenty other plants, subjected to like
conditions as the first, but without electricity; all but one died
from mildew before they were half grown, the solitary plant that
survived being only partly developed at the close of the experiment,
and even this was badly affected with the disease.

Everything considered, the results were in favor of electricity. Those
plants subjected to the greatest electrical influence were hardier,
healthier, larger, had a better color, and were much less affected by
mildew than the others. Experiments were made with various grasses,
but no marked results were obtained.

The question would naturally arise whether there may not be a limit
reached where electricity would completely overcome the attack of
mildew and stimulate the plant to a healthy and vigorous condition
throughout its entire growth. From the fact that the hardiest,
healthiest, and largest heads of lettuce grew over the greatest number
of currents and nearest the electrodes, it would seem that electricity
is one of the agents employed by nature to aid in supplying the plant
with nourishment and to stimulate its growth. To what extent plants
may be submitted to electrical influence, or what strength of current
is best suited to them and what currents prove detrimental to their
development, have not been determined as yet, but it is desirable to
continue this research until some definite information shall be gained
on these points. Probably different varieties of plants differ greatly
in their capacity for enduring the action of electric currents without
injury - experiment alone must determine this.

It has been proved that the slow discharge of static electricity
facilitates the assimilation of nitrogen by plants. Faraday showed
that plants grown in metallic cages, around which circulated electric
currents, contained 50 per cent. less organic matter than plants grown
in the open air. It would seem from the researches of the latter
physicist that those plants requiring a large percentage of nitrogen
for their development would be remarkably benefited if grown under
electric influence. - _Massachusetts Agricultural College, Bulletin No

[A very interesting article on the Influence of Electricity upon
Plants, illustrated, is given in SUPPLEMENT 806. It presents the
results of the studies of Prof. Lemstrom, of Helsingfors.]

* * * * *


By AMOS W. BARBER, M.D.,[1] Cheyenne.

[Footnote 1: Governor of Wyoming.]

Poisoned wounds, inflicted by the fangs of the rattlesnake, are
happily more rare each year, since, as the country is becoming more
populated, the crotalus is rapidly being exterminated. Yet,
considering the recklessness which characterizes the cow boy in his
treatment of this reptile, it is astonishing that this class of injury
is not more common. Thus it is the invariable custom among the
cattlemen to dismount and destroy these snakes whenever they are seen.
This is readily accomplished, since a slight blow will break the back.
This blow is, however, generally delivered by means of the quirt, a
whip not over two and a half feet long, and hence a weapon which
brings the one who wields it in unpleasant proximity to the fangs of
the reptile. A still more dangerous practice, and one which I have
frequently seen, is a method of playing with the rattlesnake for the
delectation of the cow boy at the expense of a "tenderfoot." It is
well known that unless a snake is coiled, or held by the tail or body,
or placed at length in a hole or crevice so narrow that by rendering
its length sinuous a certain amount of support is given, it cannot
strike. On this theory a mounted cow boy first puts a rattler to
flight, then pushes his pony in pursuit, stoops from the saddle,
seizes it by the tail, gives a quick upward jerk, and, swinging it so
rapidly around his head that it is impossible for it to strike, sets

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Online LibraryVariousScientific American Supplement, No. 841, February 13, 1892 → online text (page 4 of 11)