694 EXPERIMENT STATIOBT RECORD. [Vol. 37 



sewage and waste within any specified degree of depreciation or nuisance is a 

 factor of first importance. This capacity is limited by stream conditions and is 

 a function of the capacity for reaeratlon. For this reason the dilution unit is 

 an improper one for a discussion of nuisance and self-purification, and results 

 obtained upon one stream, expressed in such units, are not applicable to another. 

 Reaeration is capable of experimental determination not only in single instances 

 but in terms of general applicability. Its determination in such general terms 

 Involves laborious work of a hydraulic and analytical nature." 



The javellization of water in the field, E. Aebinet {Rev. Hyg. et Pol. Sariit., 

 39 {1917), No. 2, pp. 98-104, figs. S). — This process is described. 



A comparison of the activated sludge and the Imhoff tank trickling fi^lter 

 processes of sewage treatment, H. P. Eddy {Jour. Wesi. Soc. Engin., 21 {1D16), 

 No. 10, pp. 816-852, figs. 11; Surveyor, 51 {1917), No. 1317, pp. 370-372, figs. 2).~ 

 From a comparison of the two processes of sewage treatment It is concluded 

 that at the present time " the Imhoff tank trickling filter process is a less ex- 

 pensive means of oxidizing the organic matter of sewage wastes than the acti- 

 vated sludge process, where oxidation alone is considered. If the areas of land 

 required for isolation, the loss of head in the plant, the danger of objectionable 

 odors and of the fly annoyance, and other disadvantages of tlie trickling filter 

 process are of marked importance in any specific case, the balance may be de- 

 cidedly in favor of the activated sludge process, even in its present state of 

 development. . . . Further attention should be given to improvement in the 

 design and operation of the oldest processes of .sewage treatment." 



Marked advance in treating sewage from packing houses, G. B. Zimmeijs 

 {Engin. News-Rec, 78 {1917), No. 9. pp. 436, 437. fig. 1). — Experiments con- 

 ducted at Forth Worth, Tex., on the treatment of packing-house waste by means 

 of a small activated sludge plant showed that thl.s sewage can be succe.ssPully 

 handled by the activated sludge treatment. With reference to the fertilizing 

 value of the sludge it was found that "the addition of tlie acid hohls the 

 ammonia — contrary to the effect of adding lime. Second, the availability of tlie 

 nitrogen is increased. By the neutral permanganate method, blood cimtalns 

 about 90 per cent available nitrogen, but this treated sludge contains about 

 93.5 per cent available nitrogen." 



An experimental test of the relation of sewage disposal to the spread of 

 pellagra, J. F. Sileb, P. E. Gakrison, and W. J. MacNeal {Arch. Int. Med., 19 

 {1917), No. 5, pt. 1, pp. 683-694, figs. 2). — .\n account Is given of an experiment 

 conducted in a small milling community in South Carolina which had long been 

 a conspicuous endemic center of pellagra. In the fall of 1913 the installation of 

 a water carriage sewerage system was begun and a few houses were equipped 

 with water and fly tight pall closets. As far as possible all privies in the 

 community were made fly an^ water tight regardless of their character. 



" The diminution in new cases of pellagra in this community from 30 in 

 1913 to 18 in 1914, eight in 3915, and two in 1916 has been very remarkable, and 

 the obvious cause of this improvement would appear to be the intentional ex- 

 perimental factor, namely, the installation of the sewerage system. . . . The 

 installation of sanitary systems of sewage disposal is recommended as a meas- 

 ure for the restriction of the spread of pellagra in the general population." 



Rational and economic sanitary treatment of human wastes, F. Garbigou 

 {Compt. Rend. Acad. Sci. [Parii], 162 {1916), No. 17. pp. 640-651 ; abs. in Chem. 

 Abs., 10 {1916), No. 19, p. 2490; Internal. Inst. Agr. [Rome], Internal. Rev. 

 Sci. and Pract. Agr., 7 {1916), No. 7. pp. 947, 948).— A method of sewage treat- 

 ment considered as an economic war measure In France is described. 



The liquid and solid constituents are separated by sedimentation and decanta- 

 tion. The treatment of the liquid portion is based on the double decomposition 



