'Technical: science hax placed at' the service of man the energy looked up in coal, oil and elevated water, 0 that, as "in the old tories of magic, he hint genii to serve. him, with voetly greater powers than his own, During the past century these Yotentialities have been used to such an extent that the populations of the industrial countries and their colonies have enormously increased, while at the same time the standard of living has leon raised and the general working hours have greatly decreased. There is, however, a very distinct: limit to growth' of Population impared by agricultural considerations. The quantity of food obtainable from a certain area of Iand is Limited and, while the supply can be slightly increased by. improved biologienl knowledge and protective. measures against climatic and insect injuries, i not possible for populations indefinitely increase.
Technical science can promise increased leisure and convenience even in rather densely populated countries, but unfortunately the natural tendency of life in general, to man is no excep-which lion, is to expand numerically ax much as possible. Peace and technical knowledge have already enormously increased the _populations of India, the East Indies and Japan, and there can be little doubt that, "if a Jone peace comes to China, the sine tendency, which alrendy exists there, will be empha-seized, One hesitates to speak to engineers of birth control, but it seems lear that only a "general knowledge of that art can prevent humanity' from ultimately convert ing the benefits of mechanical science into a mere increase of numbers, without appreciable me dividual betterment. However that may be, it is the duty of the engineer to reveal and manipulate the great sources of power in Nature, Some day, the politicians condezeend to consult the engineer as to how to avoid the abuses of scientific knowledge.
China's Sources of Power which docs not leave very muck margin to the purchaser.
Primarily and fundamentally, there is sunlight. As yet, technical Knowledge has not been able to use this directly for mechanical pur-poxes in an economic way, although the maximum intensity is about 4,000 h.p. per acre. In the course of a dry hot sunny day, an area about 2 ft. square receives about ie much heat energy a8 is contained in one pound of good coal, but the lange apparatus required io ose it and the low efficiency of same iresert pi all acheings out of court except for cooking or pumping in continuously dry hot countries. Experiments have been made in Egypt and India with a certain success. In humid great deal of the solar radiation is absorbed by the moisture in the air. It appears certain that, for many' years to come, and Perhaps always, it" will in most ploces "be more economical to use sunlight for growing vegetation than to attempt to empty it directly: for power purposes.
Water power is, of course, an indirect result of sunlight nnd the consequent evaporation, dowl for: motion, and precipitation, Solar radiation, if wholly applied to causing evaporation, can convert. about} in. of water per day into vapour. There can be little doubt that water power has a most important future in China, especially in the hilly parts of the West and South, The rainfall in the North is rather erratic for this purpose. The energy of running water is, of course. largely used in the re: gulation of channels for navigation And flood control. pensive Bnergy power is another indirect result of sunlight, but is ro variable that the installation costs per unit of power are very Combined ind and water plants, in which the spasmodic wind energy is stored in the form of pumped water, may finally prove of important value, but do not offer great possibilities as yet.
Tidal-power, duo to, the earth's rotation, offers a relatively small power opportunity, Exceptionally, strong tides, such og occur in the Chientang River and the fiords of Southeast China, may be exploited to some extent, but here, again the large capital costs of installation per unit of power form a seriously adverse factor.
Wave power, due to wind and to sun-power, is spasmodic and difficult to exploit economically.
Atmospheric electricity, due to sun-power, is variable, and of minute quantity per unit' volume of air, so that it is also difficult to exploit economically.
Terrestrial heat, except obsolescent volcanic areas, is too deeply located to be usable without enornious capital expenditure, So far as I know, there are practically no volcanic areas in China which offer power possibilities.
All the above sources are. able, although practically continuous and are relatively weak, with the partial exception of -water-power. In actual fact, engineering development in China' has so far been almost entirely in regard to the liberation of solar energy chemically stored daring long per-
The Promising Resources Col containing sun-power excised through many years and preserved. in endothermic chemical forms through millions of years, is the principal source of mechanical energy. The coal resources of China are fairly well-known and the only remark that need be made hhere is that many. of the deposits: are inconveniently located, so that the cost of transport somewhat offsets the value of the materi Nothing. need be said here as to the improved methods of using coal—low temperature carbonization, pulverization, liquefaction, pro duction of " benzol, ete.—beyond. the fact.that there are still What then are the sources of power in China? In a general view, one need not consider the sources of power in other countries, since they must always he. purchased at a.priee appreciable possibilities of inoveading the efficiency of coal burning Oil—The. results of proapectiug for. rmineral.oil in China have 60, fac. byon-disapgpinting. Whatever'.
Text read from the printed page and cleaned; old type leaves the occasional error.