16 EXPERIMENT STATION EECOED, 



Is South Africa drying up? F. H. Baiu!er (Agr. Jour. Cape Good Hope, 

 36 {1910), No. 2, pp. 167-110). — The imijoverisbiiieut, detrition, and denudation 

 which have occurred in certain fertile river valleys as a result of overstocking 

 are described. 



The occurrence of ground water, C. Mezger (Jour. GashcJcucht., 52 {W09), 

 mi. 476-Ji79; J,97-500; ahs. in Wasser u. Ahwasser, 2 (1909), No. 2, pp. 86, 87; 

 Ztschr. Angeiv. Chem., 23 (1910), No. 7, />. 327).— This article discusses the 

 drainage and condensation theories of the origin of ground and spring waters, 

 but especially the bearing of variations in vapor tension in the soil and the 

 atmosphere and the conditions causing such variations on the level of ground 

 water and flow of springs. Other factors affecting the rise or fall of the level 

 of the ground water are also considered. 



Soil culture from the point of view of the underground water supply and 

 the water requirements of cultivated plants, IIitiek {BuI. Soc. A(jr. France, 

 1909, Dec. I. in>- 360-366; ahs. in Rev. Gen. Agron., n. ser.. '/ {1909), No 12, 

 pp. '/cS7-//.s'/). — This is a review of investigations by Houllier ( E. S. R., 19, 

 p. 12) from which the conclusion was reached that the lowering of the ground 

 water and the failure of springs in certain parts of France has been due to the 

 extension of the area of clean culture and has not resulted from diminished 

 rainfall, deforestation or internal erosion of soils." 



Some notes on artesian and other water supplies, L. C. Green (Queenshnid 

 Agr. Jour., 2) (1910), No. 3, pp. 103-10.), pis. 2). — The conditions necessary 

 for the occurrence of artesian water are briefly explained and the occurrence 

 of such waters in Queensland is desci'ibed. 



Analyses of mineral waters, S. D. Averitt and O. M. Siiedd (Kcnliickij Sta. 

 Rpt. 1908, pp. 1/87-503). — Analyses of samples from different parts of Kentucky 

 are reported. 



The process of self -purification of natural water after artificial inoculation 

 with bacteria, E. Sciiepilewsky <Areli. hijg., 72 (1910), No. 1, pp. 73-90). — 

 The author concludes from investigations reported in this article that as a rule 

 natural waters have bactericidal properties which enable them to free them- 

 selves quickly from bacterial contanunation. These properties are ascribed 

 to the presence and growth of protozoa. The purification of the water from 

 bacteria is dependent upon the rapidity of the growth of the protozoa. This 

 in turn results from the stimulating action on the encysted and vegetative forms 

 of protozoa of the soluble products of the autolysis of the bacteria and very 

 probably also of the products of the life activity of bacteria in general. 



The sterilization of water by the ultraviolet, E. Ukbain, C. Scal, and A. 

 Feige (Vompt. Rend. Acad. Sci. [Paris], 150 (1910), No. 9, pp. 5.'i8, 51,9).— 

 Studies of the absorption of ultraviolet rays by quartz, air, and water are 

 briefly referred to and an installation is described by which the authors suc- 

 ceeded in completely sterilizing city, sewage by subjecting it to iliunnnation for 

 one minute under an arc of 2 amperes at a distance of 10 cm. 



Disposal of Paris sewage by irrigation at Gennevilliers, Bourneville et al. 

 (Ann. Dir. ni/drauiJ. et Amelior. Agr., Min. Agr. [France], 1908, No. 37, pp. 359- 

 36 'i). — This is a brief report by the commission having charge of this work and 

 shows the amounts of sewage disposed of by irrigation in tbeConunune of Genne- 

 villiers during 1903 to 1906, as well as during the first 10 months of 1907. 



It is stated that during the first 10 mouths of 1907 the 815 hectares (2,013.9 

 acres) of land at Gennevilliers received 41,495.516 cubic meters (53,944,170.8 

 cu. yds.) of sewage water, corresponding to an annual application of 61.131 



« See also a previous article (Ann. Div. Hj'draul. et Amelior. Agr., Miu. Agr. 

 France 1907, No. 36, pp. 38-45, pis. 2, dgms. 2). 



