AGRICULTURE.
Muscular power still carries out all the most laborious work of the
farm and of the garden--work which, of course, consists, in the main,
of turning the land over and breaking up the sods. In the operations
of ploughing, harrowing, rolling, and so forth, the agency almost
exclusively employed is the muscular power of the horse guided by
man-power; with the accompaniment of a very large and exhausting
expenditure of muscular effort on the part of the farmer or farm
labourer. On the fruit and vegetable garden the great preponderance of
the power usefully exercised must, under existing conditions, come
direct from the muscles of men. Spade and plough represent the badges
of the rural workers' servitude, and to rescue the country residents
from this old-world bondage must be one of the chief objects to which
invention will in the near future apply itself.
The miner has to a very large extent escaped from the thraldom of mere
brute-work, or hardening muscular effort. He drills the holes in the
face of the rock at which he is working by means of compressed air or
power conveyed by the electric current; and then he performs the work
of breaking it down by the agency of dynamite or some other high
explosive. Much heavy bodily labour, no doubt, remains to be done by
some classes of workers in mines; but the significance of the march of
improvement is shown by the fact that a larger and larger proportion
of those who work under the surface of the ground, or in ore-reduction
works, consists of men who are gradually being enrolled among the
ranks of the more highly skilled and intelligent workers, whose duty
it is to understand and to superintend pieces of mechanism driven by
mechanical power.
In farming and horticulture the field of labour is not so narrowly
localised as it is in mining. Work representing an expenditure of
hundreds of thousands of pounds may be carried out in mines whose area
does not exceed two or three acres; and it is therefore highly
renumerative to concentrate mechanical power upon such enterprises in
the most up-to-date machinery. But the farmer ranges from side to side
of his wide fields, covering hundreds, or even thousands, of acres
with his operations. He is better situated than the miner in respect
of the economical and healthy application of horse-power, but far
worse in regard to the immediate possibilities of steam-power and
electrically-conducted energy. No one can feed draught stock more
cheaply than he, and no one can secure able-bodied men to work from
sunrise till evening at a lower wage.
Yet the course of industrial evolution, which has made so much
progress in the mine and the factory, must very soon powerfully affect
agriculture. Already, in farming districts contiguous to unlimited
supplies of cheap power from waterfalls, schemes have been set on foot
for the supply of power on co-operative principles to the farmers of
fertile land in America, Germany, France, and Great Britain. One
necessity which will most materially aid in spurring forward the
movement for the distribution of power for rural work is the
requirement of special means for lifting water for irrigation, more
particularly in those places where good land lies very close to the
area that is naturally irrigable, by some scheme already in operation
but just a little too high. Here it is seen at once that power means
fertility and consequent wealth, while the lack of it--if the climate
be really dry, as in the Pacific States of America--means loss and
dearth. But the presence of a source of power which can easily be
shifted about from place to place on the farm for the purpose of
watering the ground must very soon suggest the applicability of the
same mechanical energy to the digging or ploughing of the soil.
It is from this direction, rather than from the wide introduction of
steam-ploughs and diggers, that the first great impetus to the
employment of mechanical power on the farm may be looked for. The
steam-plough, no doubt, has before it a future full of usefulness; and
yet the slow progress that has been made by it during a quarter of a
century suggests that, in its present form--that is to say while built
on lines imitating the locomotive and the traction-engine--it cannot
very successfully challenge the plough drawn by horse-power. More
probable is it--as has already been indicated--that the analogy of the
rock-drill in mining work will be followed. The farmer will use an
implement much smaller and handier than a movable steam-engine, but
supplied with power from a central station, either on his own land or
in some place maintained by co-operative or public agency. Just as the
miner pounds away at the rock by means of compressed air or
electricity, brought to his hands through a pipe or a wire, so the
farmer will work his land by spades or ploughs by the same kind of
mechanical power. The advantages of electrical transmission of energy
will greatly favour this kind of installation on the farm, as compared
with any other method of distribution which is as yet in sight.
For the ploughing of a field by the electric plough a cable will be
required capable of being stretched along one side of the area to be
worked. On this will run loosely a link or wheel connected with
another wire wound upon a drum carried on the plough and paid out as
the latter proceeds across the field. For different grades of land, of
course, different modes of working are advisable, the ordinary plough
of a multifurrow pattern, with stump-jumping springs or weights, being
used for land which is not too heavy or clayey; a disc plough or
harrow being applicable to light, well-worked ground; and the
mechanical spade or fork-digger--reciprocating in its motion very much
like the rock-drill--having its special sphere of usefulness in wet
and heavy land. In any case a wide, gripping wheel is required in
front to carry the machine forward and to turn it on reaching the end
of the furrow. The wire-wound drum is actuated by a spring which tends
to keep it constantly wound up, and when the plough has turned and is
heading again towards the cable at the side of the field, this drum
automatically winds up the wire. So also when each pair of furrows has
been completed, the supply-wire is automatically shifted along upon
the fixed cable to a position suitable for the next pair.
Not only in the working, but also in the manuring, of the soil the
electric current will play an important part in the revolution in
agriculture. The fixing of the nitrogen from the atmosphere in order
to form nitrates available as manure depends, from the physical point
of view, upon the creation of a sufficient heat to set fire to it. The
economic bearings of this fact upon the future of agriculture,
especially in its relation to wheat-growing, seemed so important to
Sir William Crookes that he made the subject the principal topic of
his Presidential Address before the British Association in 1898.
The feasibility of the electrical mode of fixing atmospheric nitrogen
for plant-food has been demonstrated by eminent electricians, the
famous Hungarian inventor, Nikola Tesla, being among the foremost. The
electric furnace is just as readily applicable for forcing the
combination of an intractable element, such as nitrogen, with other
materials suitable for forming a manurial base, as it is for making
calcium carbide by bringing about the union of two such unsociable
constituents as lime and carbon.
Cheap power is, in this view, the great essential for economically
enriching the soil, as well as for turning it over and preparing it
for the reception of seed. Nor is the fact a matter of slight
importance that this power is specially demanded for the production of
an electric current for heating purposes, because the transmission of
such a current over long distances to the places at which the manurial
product is required will save the cost of much transport of heavy
material.
The agricultural chemist and the microbiologist of the latter end of
the nineteenth century have laid considerable stress upon the
prospects of using the minute organisms which attach themselves to the
roots of some plants--particularly those of the leguminaceae--as the
means of fixing the nitrogen of the atmosphere, and rendering it
available for the plant-food of cereals which are not endowed with the
faculty of encouraging those bacteria which fix nitrogen. High hopes
have been based upon the prospects of inoculating the soil over wide
areas of land with small quantities of sandy loam, taken from patches
cultivated for leguminous plants which have been permitted to run to
seed, thus multiplying the nitrogen-fixing bacteria enormously. The
main idea has been to encourage the rapid production of these minute
organisms in places where they may be specially useful, but in which
they do not find a particularly congenial breeding ground.
The hope that any striking revolution may be brought about in the
practice of agriculture by a device of this kind must be viewed in the
light of the fact that, while the scientists of the nineteenth century
have demonstrated, partially at least, the true reason for the
beneficial effects of growing leguminous plants upon soil intended to
be afterwards laid down in cereals, they were not by any means the
first to observe the fact that such benefits accrued from the practice
indicated. Several references in the writings of ancient Greek and
Latin poets prove definitely that the good results of a rotation of
crops, regulated by the introduction of leguminous plants at certain
stages, were empirically understood. In that more primitive process of
reasoning which proceeds upon the assumption _post hoc, ergo propter
hoc_, the ancient agriculturist was a past-master, and the chance of
gleaning something valuable from the field of common observation over
which he has trod is not very great.
Modern improvements in agriculture will probably be, in the main, such
as are based upon fundamental processes unknown to the ancients. By
the word "processes" it is intended to indicate not those methods the
scientific reasons for which were understood--for these in ancient
times were very few--but simply those which from long experience were
noticed to be beneficial. Good husbandry was in olden times clearly
understood to include the practice of the rotation of crops, and the
beneficial results to be expected from the introduction of those crops
which are now discovered to act as hosts to the microbes which fix
atmospheric nitrogen were not only observed, but insisted upon.
From a scientific point of view this concurrence of the results of
ancient and of modern observation may only serve to render the
bacteriology of the soil more interesting; but, from the standpoint of
an estimate of the practical openings for agriculture improvements in
the near future, it greatly dwarfs the prospect of any epoch-making
change actually founded upon the principle of the rotation of crops.
It is, indeed, conceivable that fresh light on the life habits of the
minute organisms of the soil may lead to practical results quite new;
but hardly any such light is yet within the inventor's field of
vision.
This view of the limited prospects of practical microbiology for the
fixing of nitrogen in plant-food was corroborated by Sir William
Crookes in the Presidential Address already cited. He said that
"practice has for a very long time been ahead of science in respect of
this department of husbandry". For ages what is known as the four
course rotation had been practised, the crops following one another in
this order--turnips, barley, clover and wheat--a sequence which was
popular more than two thousand years ago. His summing up of the
position was to the effect that "our present knowledge leads to the
conclusion that the much more frequent growth of clover on the same
land, even with successful microbe-seeding and proper mineral
supplies, would be attended with uncertainties and difficulties,
because the land soon becomes what is called clover-sick, and turns
barren".
In regard to any practical application of microbe-seeding, the farmers
of the United Kingdom at the end of the nineteenth century had not, in
the opinion of this eminent chemist, reached even the experimental
stage, although on the Continent there had been some extension of
microbe cultivation. To this it may fairly be added that some of the
attention attracted to the subject on the Continent has been due to
the natural tendency of the German mind to discover fine differences
between things which are not radically distinct. Under the title of
"microbe-cultivation" the long-familiar practice of the rotation of
crops may to some continental enthusiasts seem to be quite an
innovation!
In the electrical manures-factory the operations will be simply an
enlargement of laboratory experiments which have been familiar to the
chemist for many years. Moist air, kept damp by steam, is traversed by
strong electric sparks from an induction coil inside of a bottle or
other liquor-tight receiver, and in a short time it is found that in
the bottom of this receptacle a liquid has accumulated which, on being
tested, proves to be nitric acid. There is also present a small
quantity of ammonia from the atmosphere. Nitrate of ammonia thus
formed would in itself be a manure; but, of course, on the large scale
other nitrates will be formed by mixing the acid with cheap alkalies
which are abundant in nature, soda from common salt, and lime from
limestone.
In this process the excessive heat of the electric discharge really
raises the nitrogen and oxygen of the atmosphere to a point of
temperature at which chemical union is forced; or, in other words, the
nitrogen is compelled to burn and to join in chemical combination with
the oxygen with which formerly it was only in mechanical mixture. When
nitrogen is burning, its flame is not in itself hot enough to ignite
contiguous volumes of the same element;--otherwise indeed our
atmosphere, after a discharge of lightning, would burn itself
out!--but the continuance of an electric discharge forces into
combination just a proportionate quantity of nitrogen. Practically,
therefore, manure in the future will mean electricity, and therefore
power; so that cheap sources of energy are of the greatest importance
to the farmer.
With dynamos driven by steam-engines, the price of
electrically-manufactured nitrate of soda would, according to the
estimate of Sir William Crookes, be L26 per ton, but at Niagara, where
water power is very cheap, not more than L5 per ton. Thus it will be
seen that the cheapness of power due to the presence of the waterfall
makes such a difference in the economic aspects of the problem of the
electrical manufacture of manurial nitrates as to reduce the price to
less than one-fifth! It must be remembered that at the close of the
nineteenth century the electric installation at Niagara is by very
many persons looked upon as being in itself in the nature of an
experiment, but at any rate there seems to be no room for doubt that
the cost of natural power for electrical installations will very soon
be materially reduced. Even at the price quoted, namely L5 per ton,
the cost of nitrate of soda made with electrically combined
atmospheric nitrogen compares very favourably with commercial nitrates
as now imported for agriculture purposes. "Chili nitrate," in fact, is
about fifty per cent. dearer.
When wave-power and other forms of the stored energy of the wind have
been properly harnessed in the service of mankind, the region around
Niagara will only be one of thousands of localities at which
nitrogenous manures can be manufactured electrically at a price far
below the present cost of natural deposits of nitrate of soda. From
the power stations all around the coasts, as well as from those on
waterfalls and windy heights among the mountains, electric cables will
be employed to convey the current for fixing the nitrogen of the air
at places where the manures are most wanted.
The rediscovery of the art of irrigation is one of the distinguishing
features of modern industrial progress in agriculture. Extensive
ruins and other remains in Assyria, Egypt, India, China and Central
America prove beyond question that irrigation played a vastly more
important part in the industrial life of the ancients than it does in
that of modern mankind. This is true in spite of the fact that power
and dominion ultimately fell to the lot of those races which
originally dwelt in colder and more hilly or thickly-wooded regions,
where the instincts of hunting and of warfare were naturally
developed, so that, by degrees, the peoples who understood irrigation
fell under the sway of those who neither needed nor appreciated it. In
the long interval vast forests have been cleared away and the warlike
habits of the northern and mountainous races have been greatly
modified, but manufacturing progress among them has enabled them to
perpetuate the power originally secured by the bow and the spear. The
irrigating races of mankind are now held in fear of the modern weapons
which are the products of the iron and steel industries, just as they
were thousands of years ago terrorised by the inroads of the wild
hunting men from the North.
But the future of agriculture will very largely belong to a class of
men who will combine in themselves the best attributes of the
irrigationist and the man who knows how to use the iron weapon and
the iron implement. As the manufacturing supremacy of the North
becomes more and more assured by reason of the superior healthiness of
a climate encouraging activity of muscle and brain, so the
agricultural prospects of the warmer regions of the earth's surface
will be improved by the comparative immunity of plant and of animal
life from disease in a dry atmosphere. Sheep, cattle and horses thrive
far better in a climate having but a scanty rainfall than in one
having an abundance of wet; and so, also, does the wheat plant when
the limited rains happen to be timed to suit its growth, and the best
kinds of fruit trees when the same conditions prevail.
All this points to an immense recrudescence of irrigation in the near
future. Already the Californians and other Americans of the Pacific
Slope have demonstrated that irrigation is a practice fully as well
suited to the requirements of a thoroughly up-to-date people as it has
been for long ages to those of the "unchanging East". But here again
the question of cheap power obtrudes itself. The Chinese, Hindoos and
Egyptians have long ago passed the stage at which the limited areas
which were irrigable by gravitation, without advanced methods of
engineering, have been occupied; and the lifting of water for the
supplying of their paddy fields has been for thousands of years a
laborious occupation for the poorest and most degraded of the rural
population.
In a system of civilisation in which transport costs so little as it
does in railway and steam-ship freights, the patches of territory
which can be irrigated by water brought by gravitation from the hills
or from the upper reaches of rivers are comparatively easy of access
to a market. This fact retards the advent of the time when colossal
installations for the throwing of water upon the land will be
demanded. When that epoch arrives, as it assuredly will before the
first half of the twentieth century has been nearly past, the pumping
plants devoted to the purposes of irrigation will present as great a
contrast to the lifting appliances of the East as does a fully loaded
freight train or a mammoth steam cargo-slave to a coolie carrier.
At the same time there must inevitably be a great extension of the
useful purposes to which small motors can be applied in irrigation.
Year by year the importance of the sprinkler, not only for ornamental
grounds such as lawns and flower-beds, but also for the vegetable
patch and the fruit garden, becomes more apparent, and efforts are
being made towards the enlargement of the arms of sprinkling
contrivances to such an extent as to enable them to throw a fine
shower of water over a very large area of ground. Sometimes a windmill
is used for pumping river or well-water into high tanks from which it
descends by gravitation into the sprinklers, the latter being operated
by the power of the liquid as it descends. This mode of working is
convenient in many cases; but a more important, because a more widely
applicable, method in the future will be that in which the wind-motor
not only lifts the water, but scatters it around in the same
operation. Long helical-shaped screws, horizontally fixed between
uprights or set on a swivel on a single high tower, can be used for
loading the breeze with a finely divided shower of water and thus
projecting the moisture to very long distances. A windmill of the
ordinary pattern, as used for gardens, may be fitted with a long
perforated pipe, supported by wire guys instead of a vane, a
connection being made by a water-tight swivel-joint between this pipe
and that which carries the liquid from the pump. In this way every
stroke of the machine sends innumerable jets of water out upon the
wind, to be carried far afield.
Gardening properties in comparatively dry climates, fitted with
machines of this description, can be laid out in different zones of
cultivation, determined according to the prevailing directions of the
wind and the consequent distribution of the water supply. Thus if the
wind most frequently blows from the west the plants which require the
most water must be laid out at the eastern side, not too far from the
sprinkler. Facilities for shutting off the supply of spray at will
are, of course, very necessary. The system of watering founded on this
principle depends upon the assumption that if the gardener or the
farmer could always turn on the rain when he has a fairly good wind he
would never lack for seasonable moisture to nourish his crops. This
will be found in practice to apply correctly to the great majority of
food plants. In the dry climates, which are so eminently healthy for
cereals, "the early and the latter rains," as referred to in
Scripture, are both needed, and one of the most important applications
of cheap power will be directed to supplementing the natural supply
either at one end or at the other.
The "tree-doctor" will be a personage of increasing importance in the
rural economy of the twentieth century. He is already well in sight;
but for lack of capital and of a due appreciation of the value of his
services, he occupies as yet but a comparatively subordinate position.
Fruits, which are nature's most elaborately worked-up edible products,
must come more and more into favour as the complement to the seed food
represented by bread. As the demand increases it will be more clearly
seen that an enormous waste of labour is involved in the culture of an
orchard unless its trees are kept in perfect health. At the same time
the law of specialization must operate to set aside the tree-doctor to
his separate duties, just as the physician and the veterinary surgeon
already find their own distinctive spheres of work. The apparatus
required for the thorough eradication of disease in fruit trees will
be too expensive for the average grower to find any advantage in
buying it for use only a few times during the year; but the
tree-doctor, with his gangs of men, will be able to keep his special
appliances at work nearly all the year round.
For the destruction of almost all classes of fruit-pests, the only
really complete method now in sight is the application of a poisonous
gas, such as hydrocyanic acid, which is retained by means of a
gas-proof tent pitched around each tree. No kind of a spray or wash
can penetrate between bark and stem or into the cavities on fruit so
well as a gaseous insecticide which permeates the whole of the air
within the included space. But the gas-tight tent system of fumigation
is as yet only in its infancy, and its growth and development will
greatly help to place the fruit-growing industry on a new basis, and
to bring the best kinds of fruit within the reach of the middle
classes, the artisans, and ultimately even the very poor. Just as
wheaten bread from being a luxury reserved for the rich has become the
staple of food for all grades of society, so fruits which are now
commonly regarded as an indulgence, although a very desirable addition
to the food of the well-to-do, must, in a short time, become
practically a necessity to the great mass of the people generally.
The waste of effort and of wealth involved in planting trees and
assiduously cultivating the soil for the growth of poor crops
decimated by disease is the prime cause of the dearness of fruit. If,
therefore, it be true that the fruit diet is one which is destined to
greatly improve the average health of civilised mankind, it is obvious
that the tree-doctor will act indirectly as the physician for human
ailments. When this fact has been fully realised the public estimation
in which economic entomology and kindred sciences are held will rise
very appreciably, and the capital invested in complete apparatus for
fighting disease in tree life will be enormously increased.
Very long tents, capable of covering not merely one tree each, but of
including continuous rows stretching perhaps from end to end of a
large orchard, will become practically essential for up-to-date
fruit-culture. An elongated tent of this description, covering a row
of trees, may be filled with fumes from a position at the end of the
row, where a generating plant on a trolley may be situated. At the
opposite end another trolley is stationed, and each movable vehicle
carries an upright mast or trestle for the support of the strong cable
which passes along the row over the tops of the trees and is stretched
taut by suitable contrivances. Attached to this cable is a flexible
tube containing a number of apertures and connected at the generating
station with the small furnace or fumigating box from which the
poisonous gases emanate.
Along the ground at each side of the row are stretched two thinner
wires or cables which hold the long tent securely in position. The
method of shifting from one row to another is very simple. Both
trolleys are moved into their new positions at the two ends of a fresh
row, the fastenings of the tent at the ground on the further side
having been released, so that the flap of the tent on that side is
dragged over the tops of the trees and may then be drawn over the top
cable and down upon the other side. Seen from the end, the movements
of the tent thus resemble those of a double-hinged trestle in the form
of an inverted V which advances by having one leg flung over the
other. For this arrangement of a fumigating tent it is best that the
top cable should consist of a double wire, the fabric of the tent
itself being gripped between the two wires, and a flexible tube being
attached to each.
As progress is made from one row to another through the drawing of one
flap over the other, it is obvious that the tent turns inside out at
each step, and if only one cable and one tube were used, it would be
difficult to avoid permitting the gas to escape into the outer air at
one stage or another. But when the tubes are duplicated in the manner
described, there is always one which is actually within the tent no
matter what position the latter may be in. It is then only necessary
that the connection with the generating apparatus at the end of the
row should be made after each movement with the tube which is inside
the tent. For very long rows of trees the top cable needs to be
supported by intermediate trestles besides the uprights at the ends.
The gas and air-proof tent can be used for various other purposes
besides those of killing pests on fruit trees. One of the regular
tasks of the tree-doctor will be connected with the artificial
fertilisation of trees on the wholesale scale and for a purpose such
as this it is necessary that the trees to be operated upon shall not
be open to the outside atmosphere, but that the pollen dust, with
which the air inside the tent is to be laden, shall be strictly
confined during a stated period of time. Those methods of
fertilisation, with which the flower-gardener has in recent years
worked such wonders, can undoubtedly be utilised for many objects
besides those of the variation of form and hue in ornamental plants.