INSTITUTE. NOTES. 



The Summer's work of Section A for 1909 has been com- 

 pleted. A glance over the minutes will give some idea of the 

 different lines of investigation pursued. The meetings have 

 been held three times a month, have been well attended, and 

 the members have derived much benefit from them. The offi- 

 cers of the Section deserve much credit for their work. 



During the early part of the past Summer the residents of 

 Media were for a time much annoyed by the extremely offen- 

 sive taste and odor of its water supply. So bad did this 

 become that it was necessary to clean the reservoir, a proceed- 

 ing which remedied the trouble. The reservoir was found to 

 contain a large amount of decaying animal and vegetable 

 matter. A test of a. sample of water from the reservoir, on 

 July 25th, 1909, gave the following results : — 



Albuminoid Ammonia 305 parts per million 



Free Ammonia 105 " " 



Total Oxygen 2.5 " " " 



Nitrites I'igli 



In connection with the above, the following comparison of 

 nitrite content in reservoir, stand pipe, dam and Ridley Creek 

 is interesting. The results are given in an arbitrary scale, for 

 comparison only : — 



Dam, 5 Reservoir, 4 Creek, 2 Stand pipe, trace 

 These tests were also made on July 25th, 1909. 



The meagre rainfall of the Summer of 1909 has been most 

 remarkable. Many springheads in this locality went dry and 

 vegetation suffered very much. The balance of nature, how- 

 ever, will probably make this up to us another Summer. 

 Although there is no doubt of the evil effects of deforestiza- 

 tion, it is not probable that a sudden decrease of rainfall and 

 of underground water supply could result from this cause. 



