480 JOURNAL OF THE WASHINGTON ACADKMY OF SCIENCES VOL. 11, NO. 20 



bonate and borate buffers, respectively. The addition of salt makes 

 the buffer solutions more acid. Until more measurements on the 

 salt effect are obtained each case must be studied by itself, although it 

 is evident that the salt effect increases only slowly with increasing 

 concentrations of salt. 



From the curves it is easily seen that in order to yield the value 

 pji = 9.75 the CO2 and B2O3 should be distributed as follows in the 

 respective salts: 



CO2 



57 per cent as NaoCOs 

 43 per cent as NaHCOs 



or, as grams per liter: 



NaaCOs 5.9 

 NaHCOs 3.5 



B2O3 



C7] 



(2c 



71 per cent as Na2B204 

 29 per cent as Na2B407 



Na2B204 2.17 

 Na2B407 .68 



It is concluded that the proportions last given approximately 

 represent the concentrations of the salts that determine the alkalinity 

 of the water of Borax Lake. One factor that is not allowed for is 

 the salt effect of the carbonate buffers on the borate buffers, and vice 

 versa, but this effect is probably small compared with the salt effect 

 of the sodium chloride present which has been allowed for. By a 

 strange coincidence the percentage of total B0O3 present as borax is the 

 same as that found for vSearles Lake, but the percentage of CO2 present 

 as carbonate is 57, compared with 78 for Searles Lake. 



Below (Table 2) is given a statement of the analysis deduced 

 from the present investigation, in the form of gram ions per liter, 

 with a similar one of Searles Lake brine for comparison. The minor 

 constituents noted by Melville were not determined. 



TABLE 2 



Analyses Deduced from the Present Investigation in the Form ok Gram Ions per 



Liter 



31.58 



444.5 



