Skins, rags, bones, feathers, hair, rubber-scrap and other articles too numerous to specify were collected by this machinery. All waste arising in the slaughter of animals for food was carefully gathered. Special factories were reserved for treating the carcases of animals which had succumbed from old age, accident, disease and other causes. A farmer was not even permitted to bury the corpse of a dog. The authorities alone were vested with the power to handle deceased animals. These were thrown into suitably designed vessels, sufficiently large in some instances to receive a horse intact, which were then hermetically sealed to prevent the escape of noisome gases. Cooking was pursued to secure the fats and other products arising from the destructive distillation of the dead animal. The gases which were thrown off during the process were carefully collected, condensed to shed any foreign particles which happened to be in suspension, and then fed to the furnaces to assist in raising the heat required for cooking. By the time the distillation process had been completed only a minute quantity of fibrous residue remained together with the solid particles of bones. This mass was ground up and converted into chemical manure.
The shortage of oil was most keenly felt because this affected every range of the industrial and domestic life. Perhaps we do not generally realize the fact that all machinery would be condemned to immobility were lubricating oil supplies to be cut off. But it was not only imperative to keep the war material factories, trains, trams, motor vehicles, electric generating stations and a host of other plants in operation. Fats were in demand for a more vital issue—the table. To meet the shortage of butter, vegetable or nut-oil and animal margarine, fats and greases were in urgent request.
To mitigate the deficiency in this direction as far as possible a further rigorous enactment was put into force. It was rendered a penal offence to throw away the kernels of plums, peaches, apricots, prunes, cherries and other stone fruits or even the pips of apples and pears. One and all had to be carefully husbanded and surrendered to the authorities at special collecting stations, which, for the most part, were established in schools and municipal buildings. Juvenile effort and enthusiasm were fired. The school children were urged to maintain an alert eye for such raw material and were also encouraged to gather acorns, horse-chestnuts, and beech-nuts. The yield of such residues must have been enormous in the aggregate. One city alone reported the production of over 300,000 pounds of oil during a single year from the various nuts collected within its jurisdiction.
In the exploitation of gaseous products the Germans have undoubtedly displayed remarkable initiative. They certainly pioneered the use of the gases arising from the manufacture of pig-iron. It was the practice to allow the gases from the blast-furnaces to escape into the atmosphere. Seeing that approximately 150,000 cubic feet of gas arise from the production of a ton of pig-iron, and bearing in mind the output of the ironworks, it will be seen that the wastage in this direction must have represented a formidable item during the twenty-four hours.
These waste gases were chemically investigated, and it was discovered that approximately one-fifth of the total volume thrown off consisted of carbon monoxide gas which has a very high heating value. Thereupon the Germans set to work to recover this gas, to clean it and to convert it into a fuel for driving suitably designed gas engines. Years of labour and study were devoted to the problem, which was discovered to be exceedingly abstruse. But the obstacles were overcome and the blast-furnace gas engine made its appearance. The perfection of this means of utilizing a waste product has revolutionized a certain phase of industry throughout the world. One of the first firms to adopt the new idea was the Krupp establishment, where the gas collected from eight blast-furnaces which hitherto had been allowed to escape into and mingle with the atmosphere was harnessed to drive fifteen big engines. The perfection of this achievement in waste utilization speedily became reflected throughout the country and was subsequently introduced into this country where vast strides in connection with its use have been made.
Much has been related concerning the development of the airship in Germany, but this has been due in no small measure to the fact that it afforded a profitable outlet for the utilization of a waste product—one absolutely vital to the airship. I refer to hydrogen. This gas is produced in enormous quantities at many German works, and, for a considerable period, had to be ignored because no industrial use for it was apparent. A certain quantity was absorbed in the synthetic production of precious stones—topaz, rubies, and sapphires—but this consumption was trifling. Its fellow, oxygen, remained a drug on the market for many years until the coming of the oxy-acetylene and oxy-hydrogen method of welding and cutting metals came into popular favour. Then the demand for oxygen expanded so rapidly as to compel the laying down of plants for the production of oxygen from water by electrolysis. But the increased output of oxygen released still larger quantities of hydrogen for which practically no market obtained.
Consequently the endeavours of Zeppelin and his contemporaries received every encouragement. With the conquest of the air by the dirigible all anxiety concerning the profitable use of hydrogen disappeared. At one large factory, producing this gas in huge volumes, a special plant capable of filling the largest Zeppelin craft was laid down. The low figure at which hydrogen was obtainable was responsible in no small measure for the popularity of ballooning in Germany in days previous to the coming of the airship. The use of coal-gas for this purpose was discouraged: it was far more valuable for fuel applications, whereas the hydrogen was not only a superior lifting agent but deserved employment because it offered a remunerative outlet for a waste, and would assist in the expansion of other industries depending upon supplies of cheap oxygen.
To encourage the aeronautical use of hydrogen the firm in question embarked upon another branch of trading. It assumed the manufacture of cylinders or steel bottles for the storage of the gas under pressure—up to 200 atmospheres. Batteries of these bottles were maintained in a charged condition ready for instant dispatch to any part of the country in reply to a telegraphic or telephonic order. The airship pioneers in Germany were never in a quandary concerning the acquisition of the indispensable gas, nor were they faced with the obligation to lay down their own plants for its supply to meet their individual needs. Hydrogen was obtainable in any desired quantity at the end of a wire, and could be purchased as readily as a truck-load of coal from a colliery, while it was also available at an attractive price.
To deal fully with the German conquest of waste would prove wearisome. Enterprise and initiative are apparent in every direction from the use of recovered solder for the production of toy soldiers to the wholesale stripping of motor-cars and cheap clocks for their integral parts. Little wonder therefore that the Germans built up a wealthy national fabric. But probably the most striking evidence of the truth of the assertion that waste creates wealth is extended by the coal dye-stuffs industry. Sixty years ago the tar arising from the distillation of coal was as anathema to the engineers concerned, as I have previously related. Its disposal offered a pretty problem. It was difficult to burn, could not be turned into streams or the drains, and could not be allowed to dissipate itself into the ground. Any one who was prepared to fetch it could take it away with the engineer’s most profound blessings. It was waste in its most compelling form.
Then came Perkin with his discovery of mauve from the much-maligned tar. Immediately the former anathema of the gas-works became invested with a new and indefinable significance. But so far as Britain was concerned little progress was to be recorded. Perkin struggled valiantly to establish a new industry in this country, only to suffer discouragement and ham-stringing obstruction for his ingenuity and enterprise. The Germans appropriated the discovery and prosecuted researches and experiments so vigorously and whole-heartedly as to build up one of the biggest monopolies known to industrial effort.