Scientific Proceedings. 



(149) 85 



privy or cesspool, and in many cases there were other sources, 

 such as stables for horses and cows, pig sties, chicken yards, etc. 

 When the nitrites were as high as 0.001 parts per 100,000 the 

 water was condemned. When the nitrites ranged between 0.C003 

 and 0.001 parts per 100,000, the water was considered to be of 

 suspicious quality and warning was given to boil before using for 

 domestic purposes. In Brooklyn and Queens there are waters 

 of known purity which show nitrites as high as 0.CO03 parts per 

 100,000. Therefore, when nitrites amounting to 0.0003 parts per 

 100,000 were found, with other constituents of the water suitably 

 low, such waters were passed as fit for domestic purposes. 



It will be noticed on comparing the average figures in tables 

 A, B and C, that nitrites decrease with ammonia, and that the 

 figures for nitrates are about the same in each table. The average 

 chlorin in table C is much lower than in tables A and B, while the 

 average depths of the wells and their average distances from the 

 sources of contamination are about the same. The nitrogen aver- 

 ages in table C approach those in table D. If one takes the 

 nitrogen figures of the deep wells as a standard, the conclusion 

 may be drawn (1) that the sandy soil of Brooklyn cannot be relied 

 upon as a safe filter ; (2) that Brooklyn soil in populous districts, 

 so far as the author's evidence goes, seems to be nearing the satur- 

 ation point with sewage ; and (3) that, consequently these shallow 

 wells are in growing danger of pollution. 



44 (90). " The influence of the external temperature upon the 

 viscosity of the blood": RUSSELL BURTON-OPITZ. 



It was proved by a series of determinations that the viscosity 

 of the "living" blood can be greatly influenced by changing the 

 temperature of the surrounding medium. The viscosity was found 

 markedly increased, if the dogs used in the experiments were im- 

 mersed in water at 25 0 C. Warm water baths (42 0 C. to 45 0 C.) 

 produced a corresponding decrease in the viscosity. The specific 

 gravity of the blood was changed in a corresponding^manner. 



45 (91). "The changes in the viscosity of the blood during 

 narcosis ": RUSSELL BURTON-OPITZ. 



Determinations of the viscosity of the "living" blood were 

 made during deep and light ether and chloroform narcosis. It 



