These are some of the items of their constructive conservation programme:
Coal.—The waste in the mining of coal must be reduced from 50 and 150 per cent of the amount taken out to 25, 15, or 10 per cent by the working of upper beds first, the utilization of slack, etc. [Footnote: Van Hise, pp. 26, 27.] The reckless waste of coal in the making of coke can be prevented by the use of the right sort of oven. It is estimated that there would be a saving of $50,000,000 per annum if such a substitution were made. [Footnote: Van Hise, p. 28. ] The tremendous loss of the power value, [Footnote: Van Hise, pp. 29, 30.] from 20 to 33 per cent, and of illuminating value [Footnote: Van Hise, p. 32.] (99 per cent) in coal because of its imperfect consumption can be greatly reduced by the employment of mechanical stokers and other devices. The use of the gas- engine in the place of the steam-engine, [Footnote: Van Hise, p. 31.] the use of power developed from water, and the diffused carbon dioxide in the air tempering the climate are also intimations of forces that may lengthen the life of the coal, 99 per cent of which still remains in the keeping of the valley. It is not too late. [Footnote: See "The Coal Resources of the World," International Geological Congress, 1913.]
Petroleum.—Its probable life may be lengthened beyond ninety years by its restriction to lubricating and illuminating uses only and by the prevention of its exportation. [Footnote: Van Hise, pp. 50-55.]
Natural Gas.—Its flame is ephemeral at best, but its light may be kept burning a little longer if the prodigious waste is prevented. During 1907 four hundred billion feet were consumed and almost as great an amount wasted through uncontrolled wells, leaky pipes, etc. [Footnote: Van Hise, p. 58.]
Iron (and, in less measure, gold, silver, and other metals), whose life does not, as coal and oil and gas, perish with the using, but some of whose value is lost in the transformation from one state of use to another, needs only to be more economically mined and used. [Footnote: Van Hise, p. 68.] Non-metallic, inexhaustible materials, as stone, clay, cement, should be employed in their stead when possible. [Footnote: I watched day by day for weeks the erection of a great building in Paris, and I noticed how little iron or steel was used as compared with that in such structures in New York. We shall undoubtedly come to that.] Every scrap of iron should be conserved, cry our constructive prophets, even as the Indians treasured it. We may not need it, but succeeding generations will. It may be recast to their use. We are but its trustees. [Footnote: See, "Iron Ore Resources of the World," International Geological Congress, 1910.]
Forests[Footnote: Van Hise, pp. 223-262.]—A reduction of the waste in cutting (this is 25 per cent of the total value of the timber cut); of the waste in milling and manufacture, and in turpentining. This last waste is appalling but preventable in full or large measure. The lessening the demand for lumber by a preservative treatment of all merchantable timber. A utilization of by-products. (Undoubtedly science will be most helpful here.) Precautions against fires and their control. Reforestation. Maintenance of forests on what are called essential areas, such as high altitudes and slopes, as tending to prevent floods and erosion. (France here gives most impressive example in planning to bring under conrol about three thousand torrential streams in the Alps, Pyrenees, Ardennes, and Cévennes by means, partly at least, of afforestation, $14,000,000 out of $40,000,000 being provided for this purpose. [Footnote: Van Hise, p. 247.] Italy, because of the greatly increased destruction by the Po, has begun the reforestation of the Apennines to the extent of a million acres.) Battle with insect pests and finally the substitution of other materials for wood, thus not only saving the trees but diminishing the losses by fire.
Land. [Footnote: Van Hise, pp. 307-352.]—The control of water to prevent erosion, deep tillage, and contour ploughing. The restoration of nitrogen and phosphorus by rotation of crops, phosphates, fertilizers, and electricity. The destruction of noxious insects, mammals, and weeds. The reclamation of wet lands. The introduction of new varieties of crops.
Water.—A fuller use in the place of other sources of power that are exhausted in use. It is believed that of the twenty-six million horse- power now developed by coal fifteen million could be more economically developed by water, thus saving not only $180,000,000 by the substitution, but 150,000,000 tons of coal for posterity. [Footnote: Van Hise, p. 124.] The leading of this power through longer distances, as from Niagara Falls; its impounding for a more steady supply; [Footnote: Van Hise, pp. 125- 133.] the digging of channels of irrigation into arid places; [Footnote: Van Hise, pp. 185-207.] the drainage of wet regions; the fuller utilization of the carrying power of water to relieve the costlier use of wheels. [Footnote: Van Hise, p. 164.] Making the escaping, unsatisfying stream of Sisyphus turn the mills of the gods.
This is, indeed, as the writing of that ancient prophet of Israel who, in his vision of the restoration of his city and his land and the healing of its waters, saw a man with a radiant face, a line of flax in his hand and a measuring reed. And wherever this man of radiant face measured he caused the waters to run in dry places and deep rivers to course where the waters were but ankle-deep; fish to swarm again in the rivers and the seas to be free of pollution; salt to come in the miry places and trees to grow upon the land with unwithering leaves and abundant meat.
So have these modern prophets with optimistic faces written of their vision, only the fulfilment comes not simply of the constructive measuring of statistics. It takes some trees a hundred years to grow; and dams and reservoirs for the deepening of shallow streams are not made over night as once they were by nature, or as they grew in the vision of Ezekiel.