572 



SCIENCE 



[N. S. Vol. XLVI. No. 1197 



C. This temperature for New York City is from 

 about May fifteenth to October first; from Oc- 

 tober to May deterioration is quiescent. The de- 

 terioration of butter-fat is not due to microor- 

 ganisms but to auto-oxidation, in which the un- 

 saturated fatty acids act as oxygen carriers. The 

 process is most active for samples exposed to day- 

 light between March and September, when there is 

 a gain in weight; from September to March there 

 is a loss in weight due to volatilization of decompo- 

 sition products. Chemical action of light, which 

 is greatest about June twentieth, is a pronounced 

 factor in auto-oxidation, although temperature 

 and humidity also play an important part. 



DIVISION OF WATER, SEWAGE AND SANITATION 



E. H. S. Bailey, Chairman 

 H. P. Corson, Secretary 

 The diffusion of sea water in the Puget Sound 

 and LaTce Washington Canal: E. Victor Smith 

 and Thos. G. Thompson. The canal was con- 

 structed between Puget Sound and Lakes Union 

 and Washington to give a fresh-water harbor to 

 Seattle. A dam built to control the flow of water 

 during the cutting of the canal was swept away 

 twice, permitting sea water to enter Lake Union. 

 Three years after the second breaking of the dam 

 this lake showed a chlorine content varying from 

 5,200 parts per million at the bottom, 50 feet, to 17 

 parts at the surface. Six months later tests 

 showed a decided reduction of chlorine in the 

 upper 40 feet of Lake Union. The difference is 

 due to the inflow of fresh water from Lake Wash- 

 ington and control of tide-water by the lock sys- 

 tem. Prom considerable data authors conclude 

 that an apparently efdcient means has been intro- 

 duced by the government engineers which will pre- 

 vent the diffusion of sea water into the fresh- 

 water lakes. 



On the bactericidal efficiency of soap solutions 

 in power laundering: H. G. Elledge and W. E. 

 McBride. An investigation of the above men- 

 tioned subject conducted by the Mellon Insti- 

 tute in behalf of the Laundry Owners' National 

 Association resulted in the following conclusions: 

 The results of these experiments indicate that an 

 infusion-method for testing the bactericidal ef- 

 fect of any agent on an inoculated piece of cloth 

 must not be considered to give more than a rela- 

 tive indication of the actual number of organisms 

 present; that a count on the effluent from any 

 washing bath does not give a true indication of the 

 quantity of organism remaining in the clothes be- 



ing washed; and that plating a portion of the 

 cloth in question in agar gives a more positive in- 

 dication. They also show that soap solutions at a 

 temperature of 40° C. have a real bactericidal 

 value. Considering the omnipresence of organ- 

 isms that, under certain conditions, may be con- 

 sidered pathogenic, it appears absurd to demand 

 that a clothes-washing process should render fab- 

 rics absolutely sterile; but it has been demon- 

 strated that such results are actually obtained in 

 the case of all garments that are finished by iron- 

 ing or drying at high temperatures, and that, in 

 the case of those not so treated, the washing v?ith 

 soap produces a bactericidal efficiency comparable 

 to that obtained by pasteurization. 



Manganese in water supplies: J. W. Sale. The 

 water supply of Pierre, South Dakota, contains 2.3 

 to 3.0 milligrams per liter of manganese and 0.07 

 milligrams per liter of iron. Water mains in the 

 vicinity of the weU become clogged with a deposit 

 of oxids of manganese in a short time. Solubility 

 of the deposit in carbonated water is given. Lab- 

 oratory experiments on removing the manganese 

 are described and the general subject of man- 

 ganese in water supplies is discussed. 



RUBBER SECTION 



L. E. Weber, Chairman 

 John B. Tuttle, Secretary 



The Rubber Section of the American Chemical 

 Society held its meeting on September 12, the 

 program being as printed in the regular program 

 of the society. About 90 members and guests were 

 present. The meeting authorized the chairman and 

 secretary of the section to appoint an executive 

 committee, the purpose of this committee to be of 

 assistance to the officers in the preparation of 

 programs, meetings and such other matters as may 

 arise. It was decided that a committee should be 

 appointed, to investigate the subject of the poison- 

 ing effect of the organic accelerators used in the 

 vulcanization of rubber, the report of this com- 

 mittee to cover a list of such substances, with a 

 description of their effect on the workmen who 

 come in contact with it, and the precautions which 

 should be adopted in the mills to prevent fatal or 

 even serious injury. 



Effect of copper on crude rubier: Chas. P. Fox. 

 Reviews the work done along this line. Shows by 

 exhibit of specimens results of experiments with 

 copper acetate on crude rubber. Sustains the work 

 of Dr. Morgan, director of the Rubber Planters' 

 Association, Federated Malay States. 



