422 EXPERIMENT STATION RECORD. 



cnssinl. It is stntod tlcit siiliii'ri;r;iti(>n is (-.•isily inst:illiMl and clliciciil in ojiera- 

 lion if irivcii tlic jn'oiicr alti'iition. 



The hygienic importance of pond culture, AV. ('iu)Niikim iLdiithr. ./dlnh.. 

 38 (1009), ErfMnziiiif/sh. r>, pp. 2.13-263) .—The uso of fish ponds for the dis- 

 posal and utilization of sewage is discussed. It is shown that a certain amount 

 of sewage can be purified and profitably disposed of by turning it into fish 

 ponds and thus increasing the plant and animal growth in the ponds. 



Pond fertilizing- and purification of sewage, W. Cronheim (Ztschr. Landw. 

 Kamiiirr Schlcsirn, 13 (1909), Xo. 33, pp. 076-981). — Experiments with super- 

 ]ihosi)ha(e. sulphate of potash, and nitrate of soda, as well as with sewage, to 

 increase growth of food plants in ponds are briefly referred to and the advan- 

 tages of the ]iractice are discussed. 



Pond fertilizing. Kuhnkkt (Ztschr. Landw. Kammer 8chlcsicn, 13 (1909). 

 No. JjS, pp. I.'f57-l.'i60). — Experiments with Thomas slag, Icainit, lime, and nitrate 

 of soda are reported, and the advantages of the use of such materials in ponds 

 are discussed. 



The utilization of sewage for the production of crude oil and ammonia, 

 M. F. TuucELL (Trans. Inst. Min. Engin. [Gt. Brit.], 35 (1907-8), pi. .',. pp. 

 537-5U; obs. in Chem. Ahs., J, (1910), No. 1, p. 72).— In an effort to find some 

 better method of utilizing filter press sludge than its application as a fertilizer, 

 the author made experiments on a small scale in which the dry sludge was sub- 

 jected to distillation as in case of shalei In this way considerable amounts of 

 ammonium sulphate, crude oil suitable for gas enrichment, and a residue valu- 

 able for cement manufacture, besides combustible gases which could be utilized 

 in drying the sludge, were obtained at an estimated profit somewhat higher than 

 that obtained from shale distillation. It was found on an average that from 

 9 to 10 gal. of oil and from 57 to 65 and in some cases 100 lbs. of ammonium 

 sulphate per ton of sludge were obtained. 



SOILS— FERTILIZERS. 



Changes in the composition of the loess soils of Nebraska caused by cul- 

 tivation, F. J. Alway (Nebraska Sta. Bui. Ill, pp. 3-10). — The term loess as 

 applied to Nebraska soils is defined and the results of analyses of samples of 

 tyi)ical loess soil from different parts of the State (Antelope and Lancaster 

 counties) taken at diff'erent depths from the surface inch to the sixth foot are 

 reported. A comparison is also made of the composition of the surface soil of 

 l)rairie fields with that of adjacent long-cultivated fields of which the history 

 for 30 to 40 years is known. The average results of this comparison were as 

 follows : Potash — prairie 0.67 per cent, cultivated soil 0.65 per cent ; phosphoric 

 acid — jirairie 0.07 per cent, cultivated soil 0.07 per cent; lime — prairie 0.48 

 per cent, cultivated soil 0.48 per cent. 



The results show in general that " in their virgin condition the loess soils of 

 eastern Nebraska are rich in potash, nitrogen, humus (vegetable mold), and 

 unhumified organic matter. The supply of lime is good and that of phosphoric 

 acid is fair to good. Judged on the basis of their chemical composition these 

 loess soils would be rated very fertile and likely to long maintain their produc- 

 tive capacity if kept in good physical condition and well supplied with nitrogen 

 and organic matter. 



"The content of phosphoric acid, potash, and lime, being no lower in the sub- 

 soil than in the surface soil, no lowering of the percentages of these three con- 

 stituents is produced by the blowing away or washing away of the surface. The 

 content of nitrogen, humus, and unhumified organic matter decreases rapidly 



