












[MORAN] RADIUM STANDARD SOLUTIONS 83 
FIGURES OF MERIT. (DATES OF MCNTH GIVEN BENEATH). 
RUTHERFORD-BOLTWOOD. 
WASHINGTON. : 
Weak. Strong. 
Ie Ile if, 
lp II. III. 
6-65 6:60 6-69 | 6-42 6-41 6:58 
9 /3 11/3 16/3 | 28 /3 133 25 /3 
6-57 6:83 6:71 | 6-44 6:48 | 6:40 
17/3 | 24/3 23 3/4 27 [3 
| | (1915) 
Le OER | ERNE SEE 2 6:64 LeMay reac) Sree bese ENS De CE te cy | ng ASE aime 
Se eR LANA A rasa ntl Ree 31/3 once necro bene 
6-61 6.71 6-68 | 6:43 6-44 6-49 
TABLE oF MEANS. 
Standard. | Figure of Merit.| Percentage. 
Wiashine toner pyrene er cha SN Ponta 8 os Le 6-67 100 
Rutherford—Boltwood (Weak)............... 6:43 96-4 
Rutherford—Boltwood (Strong).............. 6-49 97-3 



As before stated, the results of last session showed— 
Rutherford—Boltwood Weak 
Rutherford—Boltwood Strong 
: Washington :: 98 : 100. 
: Washington :: 96 : 100. 
while Rutherford himself found the solid standard 4-9% low with! the 
International and also with the Vienna Standards. 
have 
Rutherford—Boltwood Solid Standard : Washington 
Hence we also 
Se WO) cal 100. 
It will be noted that the present results differ somewhat from those of 
last year. 
In the case of the strong solution the mean of the results 
of last year and of this year are taken, owing to one of the solutions 
being discarded. The close agreement of duplicate results in the one 
case and of triplicate results in the other for the Rutherford—Boltwood 
weak and the Washington standard solutions puts their validity 
above question. 
