Page:Popular Science Monthly Volume 58.djvu/676

668 of alkali in the soil and its causes, means of ameliorating these conditions, and similar problems relating to alkali soils. A variety of local conditions were met with, which call for specific treatment. In a number of regions reconnoitered, the present accumulation of alkali, which has frequently nearly reached the limit of tolerance of plants, is attributed to lack of good natural drainage. The evaporation in these arid or semi-arid regions is unusually great, and with insufficient rainfall and injudicious irrigation tends to an accumulation of the alkali salts near the surface. With good natural drainage and proper application of irrigation water these salts would be in a measure washed out of the soil and the soil moisture maintained at nearly the same concentration as the water supply. But, in some cases, the irrigation water itself has become so charged with alkali as to call for the exercise of judgment in its use. "It may be perfectly safe to use water of a relatively high salt content on certain well-drained soils, when it would be ruinous to allow the same water to be used on a properly-drained soil containing a high salt content." The maps which accompany the report make it possible to determine the limit of the salt content of the water which it would be safe to use in the localities reconnoitered. The seepage waters are mentioned as another frequent cause of increase of the alkali in the soil. For instance, in the Salt Lake Valley, the oldest of the modern irrigated districts, the lower levels, which were formerly the most productive soils of the valley, have been damaged and in some cases ruined by seepage waters and alkali. In general, where the conditions are favorable and the expense would be warranted, underdrainage with tile is recommended as a remedy for excessive alkali in the soil. This remedy is considered entirely practical for reclaiming extensive areas, which at present have become nearly or quite worthless.

record with regret the following deaths, which have occurred during the month: Dr. George M. Dawson, the eminent director of the Geological Survey of Canada, died on March 2 at the early age of fifty-one years, after an illness of only two days. He was well-known for his important contributions to the geology of Canada and for his conduct of the geological survey and of various commissions. Prof. G. F. Fitzgerald, who has held since 1881 the chair of experimental philosophy in the University of Dublin, and is well known for his researches on magnetism and in other directions, died on February 21 at the age of forty-nine years. Dr. Walter Myers died from yellow fever in Brazil, whither he had gone from the Liverpool School of Tropical Medicine to investigate the disease. He was only twenty-nine years of age. Dr. Jacob Georg Agardh, the eminent Swedish phycologist, died at Lund, on January 17, aged eighty-eight years. The death is also announced, in his seventieth year, of Dr. Bernhardt Danckelmann, for the last thirty-five years director of the Prussian Royal Academy of Forestry at Eberswalde. He was one of the first to advocate the training of foresters in special colleges, and was the author of important works on forestry.—The degree of LL.D. has been conferred by St. Andrew's University on Mr. Alexander Agassiz, of Harvard University, and by the University of Pennsylvania on President Henry S. Pritchett, of the Massachusetts Institute of Technology.—The Cullum Medal of the American Geographical Society has been conferred on President T. C. Mendenhall, of the Worcester Polytechnic Institute.—The Amsterdam Society for the Advancement of Natural Science and Medicine has awarded its gold Swammerdam medal for 1900 to Professor Gegenbaur, of Heidelberg.—Mr. J. E. Spurr, of the U. S. Geological Survey, has accepted an invitation of the Turkish Government to make an investigation of the mineral resources of the country.