5. Water Salinity . Tlie following record of salinity of the 

 water (as sodium chloride in parts per million), made at various times 

 each month, shows the general range throughout the year at each location. 



6. Hydrogen-Ion Determination . The following record of pH 

 determination of the water, made at various times each month, shows the 

 general range throughout the year at each location. 



188 



