408 PROCEEDINGS OP THE AMERICAN ACADEMY. 



solution of hydrocliloric acid used in all the exjieriments was 0.009074* 

 normal; that of nitric acid was 0.010145 t normal. The cell constant 

 or capacity of the resistance vessel (that is, the ratio of the specific con- 

 ductance of any solution to its actual conductance as measured in the 

 vessel) was 0.11059. J 



The following tables contain the results of the separate series of ex- 

 periments. As headings are given, the weight in grams (?«„,) of water 

 taken, its actual conductance {L^) multiplied by 10" when measured in 

 the vessel, and its specific conductance («„) multiplied by lO*'. The first 

 column gives the number of the portions of standard acid or potassium 

 chloride solution which Avere added; the second gives the total weight 

 of the added portions; the third, the concentration (c) of the resulting 

 solution in milliequivalents per liter (see Section II) ; the fourth, the 

 conductance in reciprocal ohms measured in the resistance vessel and 

 multiplied by 10**; the fifth, the equivalent conductivity of the acid 

 calculated by subtracting from the specific conductance of the solution 

 (kj) that of the water and dividing the difference by the concentration 

 i. e. (k^ — Kv^jc. In the sixth and seventh columns are given the cor- 

 rected values of the equivalent conductivity computed by the first method 

 described in Section IV, taking for the initial concentration that corre- 

 sponding to the first and second added jiortions, respectively. In the 

 oightli column are given the corrected values of the equivalent conduc- 

 tivity calculated by the second method described in Section IV. (In 

 tlie case of the potassium chloride series these are replaced by the equiva- 

 lent conductivities obtained by Kohlrausch and ]\Ialtby.) 



* This result was based upon four determinations, of which the data were as 

 follows: 



Grams HCl solution taken 340.27 328.60 347.70 356.38 



Grams AgCl obtained 0.4506 0.4277 0.4521 0.4623 



Equivalents per 1000 grams sol. 0.009076 0.009078 0.0090G8 0.009047 

 The last on account of its great deviation was omitted in taking the mean. 



t This solution was obtained by dilution (by weight), of a 0.05 normal solution 

 which has been standardized against a 0.1 normal solution of recrystallized barium 

 hydroxide, the titration values showing an average deviation of 0.03 per cent from 

 their mean. The barium hydroxide was standardized by neutralizing it with 

 nitric add, evaporating, drying at 170°, and weighing as Ba(N()3)o, and also pre- 

 cipitating it with sulphuric acid, filtering out, igniting, and weighing the BaSO^. 

 The average deviation from the mean of the four determinations by those two 

 metliods was 0.05 percent. 



t This was the mean derived from measurements with five distinct 0.01 normal 

 potassium chloride solutions containing 7455 grams KCl weighed in air, in 1000 

 grams water: the average deviation of tlie five values from the mean was 0.03 

 per cent. 



