SOILS FERTILIZERS. 115 



are jjcivon wliich suniniarize the results of (jbservatioiis on rainfall at over 200 

 stations in the colony during the year ended June 30, 1!)0S. Temperature and 

 pressure records for a limited number of stations during the same period are 

 also given. 



Studies on the phenomena of the evaporation of water over lakes and 

 reservoirs, F. H. Biuelow (Mo. Weather Rev., 36 (1908), A'o. 13, pp. Ji31l-l',5, 

 pg. I). — This is a fourth paper on this subject ( E. S. li., 10, p. 1112), and deals 

 with the progress in 1908 and proposed extension of the work, together with 

 an analysis and application of the evapoi'ation formula with special reference 

 to observations at Indio and Mecca, Cal. 



The significance of Bacillus coli in potable waters, Guiraud and H. 

 Maudoul {Ann. Inst. PiLsteur, 22 (JOOS), No. 11, pp. 917-926, figs. 2).— This is 

 an article based upon studies of the water supply of Toulouse, the general con- 

 clusion fi'om which is that the presence of the coli bacillus in the water supply 

 is intimately connected with the existence of causes of contamination. Its 

 abundance is directly related to the importance of these causes. While the 

 bacillus itself does not constitute a grave danger, it furnishes a valuable index 

 of infection. 



The I'ole of septic tanks in the biological purification of sewage water, 

 A. MiJNTz and E. Laine {Conipt. Rend. Acad. Sci. [Paris], US {1909), Xo. 10, 

 pp. 597-601). — The most useful role of septic tanks in these experiments ap- 

 peared to be as a means of decantation of matter in suspension. It is thought 

 that it might be profitable to inquire whether some less cumbersome and costly 

 method of accomplishing this result may not be devised. 



SOILS— FERTILIZERS. 



Inquiry into the causes of the decrease in fertility of some soils in the 

 Groningen and Drenthe moor colonies, B. Sjollema and J. Hudig {Versing. 

 Lundhoinrk. Onderzoek. RijksJandhoun-proefstat. [yetlierlands], 1909, No. 5, pp. 

 29-157, 2)ls. 2, dgms. 11). — The investigation of which this is a preliminary report 

 was begun in 1005 with field observations to determine in a general way the 

 nature and extent of the so-called " oat sickness." 



It was found that for several years the productive power of certain fields in 

 the Groningen and Drenthe moor colonies had been decreasing; oats was the 

 crop chiefly affected, but rye and potatoes have also suffered. In the case of 

 oats, usually in the month of May, the leaves gradually turn yellow and have a 

 sick appearance ; withered spots appear on the leaves and the affected leaves 

 fold and droop. Following the field observations field and culture tests were 

 carried on at the Groningen Experiment Station. 



It is concluded from the results of 3 years' tests that the unhealthy proper- 

 ties of the moor-colony soils are due to faulty treatment, especially as regards 

 fertilization. As a rule the application of too much lime or calcareous fertilizers 

 is a cause of sickness, while physiologically alkaline fertilizers (as nitrate of 

 soda) and also fertilizers which increase the production of alkaline humates are 

 unfavorable. By such treatment the properties of the soil are modified in vari- 

 ous respects ; besides neutralizing the original acid reaction, changes take place 

 in the behavior of the organic constituents (humate-silicate compounds), espe- 

 cially toward oxygen. 



On soils still normal care must be observed in the application of such fer- 

 tilizers and on soils already unfavorably affected these fertilizers must be 

 avoided or at least alternate applications of acid and physiologically acid fer- 

 tilizers must be made. 



