The Javanese seem to have obeyed the command: Be ye fruitful and multiply; bring forth abundantly in the earth and multiply therein. (Gen. 10: 7.) Whether such an enormous increase is desirable, is a debatable question, for the natural methods of controlwarfare, plagues, and decreasing fertility of soil-have been held in abeyance by scientific control on the part of the Dutch. Efforts have been made to encourage emigration to the less densely populated island of Sumatra, but such is the attachment of the Javanese to his native soil that only by force can he be uprooted.

A careful study has been made of the amount of land required for raising the food crops of the natives and of the optimum area that should be devoted to the raising of crops for export. Such crops are a source of revenue for the owners and also provide gainful occupation for the natives. The volcanic soil of Java differs from that of Central America in that it is derived from the decomposition of ferruginous, andesitic, and basaltic lavas. Much of the soil has been brought down from the steep slopes of the volcanoes and deposited in the wash plains. This ferruginous lava alters to a soil that is pervious but contains claylike minerals that retain much of their moisture during the dry season. This lateritic soil peculiar to the wash plains that lie between the volcanic edifices is the basis of Java's magnificent agricultural achievement. It not only has the physical properties peculiar to porous materials of exposing a large surface to the atmospheric agencies, oxygen and carbon dioxide, but it also contains fair amounts of potash and phosphates. The volcanic activity of the present day also contributes to the rejuvenation of the soil, as can be readily seen on the volcano of Merapi in middle Java. The red, finely comminuted lava poured out on its slopes is easily washed down into the plains by the heavy rains of the wet season. The natives and the Dutch have early recognized the dangers of soil erosion in intensively cultivated areas and have combated them in their rice culture through an efficient system of terracing in the embayments of the volcanoes. The result is not only successful but is also a distinct contribution to the beauty of the landscape. Java has been aptly named the Garden of the East. Such is the fertility of the soil and so thoroughly is the water conserved that in the Preanger district three crops of rice can be raised in a year.

We have seen above that volcanic areas subject to alternating wet and dry seasons have flashy streams which carry much virgin and potential soil from the slopes of the volcanoes. The Dutch have realized the necessity for conserving their water supply and in consequence have made the hydrological service one of the most important in the island. One sees the explanation of the persistence of the fertility of the soil in the muddy waters of the great network of irrigation ditches. An interesting example which illustrates the acumen

of the Dutch scientists in Java is shown by the manner in which the : destructive action of the acid waters issuing from the crater lake of Kawah Idjen was neutralized. A survey of the waters draining the valley below the crater was made and a stream was found whose alkaline waters could be combined with the acid waters from Kawah Idjen. The combination yielded a water which could be utilized for purposes of irrigation.

Mention should be made of the excellent scientific work of the medical men who early discovered that the dread disease beriberi was caused by eating hulled rice and of the efforts to hold in check the many plagues that usually harassed the population; mention should also be made of the extensive agricultural experiment stations supported by both the Government and the planters. New species of disease-resisting coffee bushes and sugar have been studied and furnished to the natives and the planters. More prolific species of rubber trees have been discovered. Extensive studies have been made of the volcanic soils and the mixed sedimentary and volcanic soils in order to learn what crops can be most readily cultivated in them. Mention should be made of the extensive archeological studies carried out by the Dutch in Java. All these matters bear only indirectly on the volcanic activity, but they illustrate what can be accomplished by the application of coordinated knowledge.

Before bringing this essay to a close I should like specifically to call attention to the efforts now made by the Geological Survey of Java to offset the decreased demand for their chief crops, namely, rubber, sugar, tea, coffee, and tapioca; little or no rice is exported since all is needed for home consumption. An intensive search is being made by the Survey to locate mineral deposits and exploit more thoroughly those already discovered. Finally, credit must be given to the Dutch in the East Indies for their willingness to carry the burden of pure research during the present period of economic distress. Special mention should be made of the fact that Java is the only government which at the present time supports an efficient volcanological service devoted to the collection of facts which they hope can be used in mitigating the effects of volcanic and seismic manifestations.

The writer may be a bit daft on the subject of Java, but a sojourn of four months in 1928 has left the indelible impression that here the world can watch the results of a carefully planned and scientifically controlled large-scale experiment in geographical adaptation. It would behoove the world to permit this experiment to continue under the present control. Others more competent than myself to judge of the efforts of the Dutch concur in this opinion.

I have somewhat sketchily, to be sure, outlined how scientific endeavor can be utilized by the coordinating thread of human geography to promote human welfare, and it is now fair to ask the question

that the younger generation is fond of putting to us: Well, what of it? If we persist for generations to come in following an insane type of personal and nationalistic ambition, and if we make no effort to overcome mental inertia, then the answer to the question posed by our youth is: Nothing. If, however, the possibilities of scientific endeavor in promoting human welfare are generally realized, then I believe all of us will have made a step forward out of our present Slough of Despond. The writer is not so naive as to suppose that this great desideratum can be brought about over night.

I am reminded in this connection of the motto of Nuñez de Balboa, who had accomplished much but wished that he could have done more. This sentiment he expressed by the words: "Llega el hombre hasta donde puede y no hasta donde quiere." *

*Man gets as far as he can and not as far as he wishes.

LOS VOLCANES Y LA GEOGRAFÍA HUMANA

por

EL DR. E. G. ZIES

Laboratorio de Geofísica de la Institución Carnegie de Washington

(Resumen)

Jean Brunhes ha dicho que la geografia humana es el estudio de las relaciones entre las actividades humanas y los fenómenos de la geografía física.

Gran número de zonas volcánicas están situadas en latidudes tropicales y sub-tropicales y su densidad de población causa sorpresa si se consideran los peligros que ofrecen los volcanes y los fenómenos sísmicos característicos de esas regiones.

El autor de este trabajo hará todo lo que esté a su alcance para avaluar las condiciones existentes en los alrededores de esas zonas en términos de felicidad humana.

337

THE RELATION OF EARTH PHYSICS TO GEOGRAPHICAL

PROGRESS
by

DR. J. A. FLEMING

Director of the Department of Terrestrial Magnetism of the Carnegie Institution of Washington

General Secretary of the American Geophysical Union

The challenge of surface geography has been met practically in the attainment by man of the geographic poles and by his conquest of nearly all "unexplored" regions. Now the greater and equally intriguing challenge of the application of scientific research to geography-as truly adventure as the overcoming of natural obstacles is receiving that increased attention it so merits. Geographical progress has always been stimulated, but more particularly so in recent times, by those natural phenomena which find explanation in physical laws. Nowhere are the potential contributions of pure research to geography better indicated than in investigations of earth physics, that is, geophysics. With her usual prodigality Nature produces for our interpretation and analysis almost continuously series of varied experiments in our greatest laboratory, the earth.

The intimate relations between the problems of our life and environment and geophysics are immediately apparent upon considering the spheres included in its subdivisions. These are geodesy, seismology, volcanology, meteorology, hydrology, oceanography, and terrestrial magnetism and electricity.

We may first cite geodesy, which has to do with the shape and size of the earth. Without geodetic work it would not be possible to property record on maps in their relative positions the findings of geographers. Here modern developments in physics have made possible greatly improved technique. Whereas several decades ago a gred paphe survey took several seasons of Seidwork, like survers of greater precision may now be sccomplished in weeks or even days by serial photography, so grudy advanced by physical erris Where beretofore the geographer had to depend, over long marvak upon the cermines of standard reference meridian $ sà a C-med by chronometers and always MUŽJAT NO LIOErazy because of maceracies resulang from feult