458 ABSTRACTS 



complaints have been noted with Hquid CI. With intelUgent opera- 

 tion the plants afford a cheap method of treatment for supplies not 

 requiring filtration, and cause a marked decrease in typhoid. — L. P. 



Copper Sulfate Treatment of St. Paul, Minnesota Water Supplies. N. L. 



Huff and G. 0. House. J. Am. W. W. Assoc, 1916, 3, 581-621. 



One part per 12,000,000 parts of water was found to be adequate 

 to eliminate Spirogyra, Cyclotella and most Cyanophyceae. One part 

 per 10,000,000 remained effective for five weeks after which time 

 treatment was repeated. Charts accompany the paper. — F. W. T. 



The Water Supplies of Interstate Common Carriers on the Great Lakes. 



H. P. Letton. J. Am. W. W. Assoc, 1916, 3, 364-384. 



Letton discusses mechanical features of the subject together with 

 various methods for treatment of such water. Bacteriological analyses 

 were made according to the method promulgated by the Secretary 

 of the Treasury (Public Health Reports, November 6, 1914, p. 2960). 

 From these bacterial examinations Letton considers it an impossibility 

 to obtain a drinking water for boats directly from the lakes that will 

 at all times conform to the Treasury Department standard. — F. W. T. 



The Use of Ammonia in the Chlorination of Water. Joseph Race. 



Can Engr., 1916, 30, 345-346. 



Ammonium hypochlorite proved to have a very rapid action, 20 

 to 30 times as rapid as CaOCla. The ammonium salt is not absorbed 

 readily, preventing after-growths. The use of ammonia (aqua 16°B.) 

 with CaOCl2 may be economical when the CaOCl2 costs over $2.08 

 per 100 pounds. Difficulties in application require quick mixing with 

 large dilution after ammonia is added to bleach solution to avoid loss. 



L. P. 



Some Aspects of Chlorination. Joseph Race. J. Am. W. W. Assoc, 



1916, 3, 439-449. 



Among other subjects Race discusses the questions of aftergrowths 

 and types of B. coli which survive chlorination. Much difference of 

 opinion exists with regard to the question of aftergrowths. The after- 

 growths, under usual working conditions, vary according to the dosage 

 of chlorine employed. A small amount .^f chlorine exerts a selective 

 action. With large amounts a flora of spore formers survives which 

 is unlike the original flora of the water. A study to determine whether 

 the B. coli found after chlorine treatment were more resistant, indicated 

 that there was little difference in the resistance of various types to 

 chlorine.— F. W. T. 



A Study of Some Organisms Which Produce Black Fields in Aesculin — 

 Bile-Salt-Media. F. C. Harrison and J. Vanderleck. With 4 

 plates. Trans. Roy. Socy. Can., 1915, Ser. Ill, 9, Sec IV, 207-217. 

 Six hundred pure cultures were isolated from aesculin bile-salt-agar, 



and lactose htmus agar plates made during analyses of 1000 milk sam- 



