1917] KURAL ENGINEERING. 889 



Nitrites in potable water, A. A. Bado and V. J. Beenaola (An. Soc. Quim. 

 Argentina, 4 {1916), No. 15, pp. 251-255). — The works of others bearing on the 

 subject are briefly reviewed, and it is concluded in view of the results obtained 

 by the authors that the importance of the presence of nitrites in drinking water 

 is exaggerated. It is considered more important to determine the source of the 

 nitrites, if any exist. 



Purification of drinking' water with calcium hypochlorite, A. A. Bado and 

 L. Dasso {An. Soc. Quim. Argentina, 4 {1916), No. 15, pp. 242-250). — The work 

 of others bearing on the subject is reviewed and experiments on the purifying 

 action of calcium hypochlorite on polluted river water are reported. 



A 10 per cent solution of calcium hypochlorite containing 16 per cent of active 

 chlorin was used. This was added to the water at rates of 0.05, 0.1, and 0.15 

 cc. per 1,000 cc. of water. Bacteriological examinations were made one, two, 

 and five hours after treatment. Better results were obtained with this treat- 

 ment from the bacteriological point of view tlian previous experimenters had 

 obtained with a treatment with 0.015 gm. of calcium hypochlorite containing 

 35 per cent of active chlorin. The coli bacilli disappeared completely and the 

 numbers of other objectionable organisms, which were numerous in the raw 

 water, were reduced until almost negligible. 



Further experiments in which 1, 2, and 3 cc. of calcium hypochlorite solution 

 were used and examinations made after one, three, six, and nine hours showed 

 that the diminution in numbers of objectionable organisms as related to that 

 of the previous experiments was less in proportion to the amount of hypo- 

 chlorite used. Experiments on the effect of calcium hypochlorite and aluminum 

 sulphate when used together are also reported. 



The results as a whole are taken to indicate that calcium hypochlorite is very 

 effective in the destruction of coli, Eberth, and pyocyaneus bacilli, and that 

 small doses diminish the vitality of these organisms. In cases requiring a 

 relatively high active chlorin content (33 per cent) and a relatively short time 

 of contact appreciable results have also been obtained. Baciilns subtUis was 

 found to be more resistant to this action. 



Sixth biennial report of the state highway commissioner of Washington, 

 Oct. 1, 1914, to Sept. 30, 1916, J. Allen {Bien. Rpt. State Higliivay Comr, 

 Wash., 6 {1915-16), pp. 123, pis. 6). — The work and expenditures of the Wash- 

 ington state highway commission for this period are dealt with. 



Third annual report of the country roads board of Victoria {Ann. Rpt. 

 Country Roads Ed. Victoria, 3 {1916), pp. 10, figs. 20).— This is the third annual 

 report of the board, dealing with permanent works completed and in progress, 

 road-making machinery, motor-car registrations, investigations, and finances. 



Regulations respecting highways, 1916, W. A. McLean {Ontario Dept. 

 Pub. Highways Ann. Rpt., 1916, App., pp. 11). — The text of the regulations is 

 given. 



Road construction for township road superintendents and overseers, W. A. 

 McLean {Ontario Dept. Pub. Highways Ann. Rept., 1916, App., pp.12, figs. //). — 

 This is a brief manual of instructions as to the essential features and consid- 

 erations in the construction of the ordinary country roads. 



County roads, F. G. Macdiarmid {Ontario Dept. Pub. Hightcays Ann. Rpt., 

 1916, App., pp. 7). — The general features of the organization and construction 

 of a county road system under Canadian highway improvement laws are briefly 

 outlined. 



Helpful suggestions for svirveying country highways, S. P. Baikd {Engin. 

 News, 77 {1911), No. 5, pp. 180-182, figs. 3).— Some suggestions on special 

 survey methods and devices from the practice of an experienced surveyor are 

 given. 



