It is clear that in the adoption of the succulent forms of vegetables as human food important advantages are gained. At this stage of maturity they have a higher digestibility, thus making the elimination of the animal less difficult. Their nitrogen content is relatively higher and this in a measure compensates for loss of meat. By devoting the soil to growing vegetation which man can directly digest they have saved 60 pounds per 100 of absolute waste by the animal, returning their own wastes to the field for the maintenance of fertility. In using these immature forms of vegetation so largely as food they are able to produce an immense amount that would otherwise be impossible, for this is grown in a shorter time, permitting the same soil to produce more crops. It is also produced late in the fall and early in the spring when the season is too cold and the hours of sunshine too few each day to permit of ripening crops.
VII
THE FUEL PROBLEM, BUILDING AND TEXTILE MATERIALS
With the vast and ever increasing demands made upon materials which are the products of cultivated fields, for food, for apparel, for furnishings and for cordage, better soil management must grow more important as populations multiply. With the increasing cost and ultimate exhaustion of mineral fuel; with our timber vanishing rapidly before the ever growing demands for lumber and paper; with the inevitably slow growth of trees and the very limited areas which the world can ever afford to devote to forestry, the time must surely come when, in short period rotations, there will be grown upon the farm materials from which to manufacture not only paper and the substitutes for lumber, but fuels as well. The complete utilization of every stream which reaches the sea, reinforced by the force of the winds and the energy of the waves which may be transformed along the coast lines, cannot fully meet the demands of the future for power and heat; hence only in the event of science and engineering skill becoming able to devise means for transforming the unlimited energy of space through which we are ever whirled, with an economy approximating that which crops now exhibit, can good soil management be relieved of the task of meeting a portion of the world's demand for power and heat.
When these statements were made in 1905 we did not know that for centuries there had existed in China, Korea and Japan a density of population such as to require the extensive cultivation of crops for fuel and building material, as well as for fabrics, by the ordinary methods of tillage, and hence another of the many surprises we had was the solution these people had reached of their fuel problem and of how to keep warm. Their solution has been direct and the simplest possible. Dress to make fuel for warmth of body unnecessary, and burn the coarser stems of crops, such as cannot be eaten, fed to animals or otherwise made useful. These people still use what wood can be grown on the untillable land within transporting distance, and convert much wood into charcoal, making transportation over longer distances easier. The general use of mineral fuels, such as coal, coke, oils and gas, had been impossible to these as to every other people until within the last one hundred years. Coal, coke, oil and natural gas, however, have been locally used by the Chinese from very ancient times. For more than two thousand years brine from many deep wells in Szechwan province has been evaporated with heat generated by the burning of natural gas from wells, conveyed through bamboo stems to the pans and burned from iron terminals. In other sections of the same province much brine is evaporated over coal fires. Alexander Hosie estimates the production of salt in Szechwan province at more than 600 million pounds annually.
Coal is here used also to some extent for warming the houses, burned in pits sunk in the floor, the smoke escaping where it may. The same method of heating we saw in use in the post office at Yokohama during February. The fires were in large iron braziers more than two feet across the top, simply set about the room, three being in operation. Stoves for house warming are not used in dwellings in these countries.
In both China and Japan we saw coal dust put into the form and size of medium oranges by mixing it with a thin paste of clay. Charcoal is similarly molded, as seen in Fig. 72, using a by-product from the manufacture of rice syrup for cementing. In Nanking we watched with much interest the manufacture of charcoal briquets by another method. A Chinese workman was seated upon the earth floor of a shop. By his side was a pile of powdered charcoal, a dish of rice syrup by-product and a basin of the moistened charcoal powder. Between his legs was a heavy mass of iron containing a slightly conical mold two inches deep, two and a half inches across at the top and a heavy iron hammer weighing several pounds. In his left hand he held a short heavy ramming tool and with his right placed in the mold a pinch of the moistened charcoal; then followed three well directed blows from the hammer upon the ramming tool, compressing the charge of moistened, sticky charcoal into a very compact layer. Another pinch of charcoal was added and the process repeated until the mold was filled, when the briquet was forced out.
By this simplest possible mechanism, the man, utilizing but a small part of his available energy, was subjecting the charcoal to an enormous pressure such as we attain only with the best hydraulic presses, and he was using the principle of repeated small charges recently patented and applied in our large and most efficient cotton and hay presses, which permit much denser bales to be made than is possible when large charges are added, and the Chinese is here, as in a thousand other ways, thoroughly sound in his application of mechanical principles. His output for the day was small but his patience seemed unlimited. His arms and body, bared to the waist, showed vigor and good feeding, while his face wore the look of contentment.
With forty centuries of such inheritance coursing in the veins of four hundred millions of people, in a country possessed of such marvelous wealth of coal and water power, of forest and of agricultural possibilities, there should be a future speedily blossoming and ripening into all that is highest and best for such a nation. If they will retain their economies and their industry and use their energies to develop, direct and utilize the power in their streams and in their coal fields along the lines which science has now made possible to them, at the same time walking in paths of peace and virtue, there is little worth while which may not come to such a people.
A Shantung farmer in winter dress, Fig. 18, and the Kiangsu woman portrayed in Fig. 73, in corresponding costume, are typical illustrations of the manner in which food for body warmth is minimized and of the way the heat generated in the body is conserved. Observe his wadded and quilted frock, his trousers of similar goods tied about the ankle, with his feet clad in multiple socks and cloth shoes provided with thick felted soles. These types of dress, with the wadding, quilting, belting and tying, incorporate and confine as part of the effective material a large volume of air, thus securing without cost, much additional warmth without increasing the weight of the garments. Beneath these outer garments several under pieces of different weights are worn which greatly conserve the warmth during the coldest weather and make possible a wide range of adjustment to suit varying changes in temperature. It is doubtful if there could he devised a wardrobe suited to the conditions of these people at a smaller first cost and maintenance expense. Rev. E. A. Evans, of the China Inland Mission, for many years residing at Sunking in Szechwan, estimated that a farmer's wardrobe, once it was procured, could be maintained with an annual expenditure of $2.25 of our currency, this sum procuring the materials for both repairs and renewals.