78 THE ROYAL SOCIETY OF CANADA 
standard was found to be 4-9% low. Hence it was also to be expected 
that the solution standards would come out similarly if no error 
was made in their preparation. As a considerable amount of work 
has been done on the amount of emanation in air, and on the relative 
amounts of radium and uranium in rocks and water, the importance 
of knowing the correct values of these solution standards is evident. 
In the course of the work referred to, it was for a long time diffi- 
cult to get concordant results. It appeared on the evidence of the 
results of the observations taken over a long series of experiments 
_ that the solutions generally deteriorated in strength. The addition 
of some HC1 to one of the solutions which had been boiled a number 
of times seemed to cause a higher reading. It was discovered later 
that the HC1 used was itself radioactive, and that part at least 
of the increase was due to this cause. The balance of the increase 
was at that time set down to some of the radium salt being deposited 
from the solution in a “‘de-emanating’’ condition by boiling. In 
the latter part of this work the results obtained were more satisfactory, 
and the mean of several close results showed— 
Rutherford—Boltwood Strong Solution : Washington :: 96 : 100. 
Rutherford—Boltwood Weak Solution : Washington :: 98 : 100. 
Refs. Phil. Mag., Oct., 1915. J. Moran. 
Radioactive Substances and their Radiations. Rutherford. 
OBJECT OF THIS WORK. 
This work was undertaken— 
(1) To study the causes of variation in some of last year’s work, 
and to confirm or qualify the results then obtained. 
(2) To determine if the solutions really deteriorated by boiling 
and if so, whether it was due to 
(a) Deposition of the radium salt in a ‘‘de-emanating”’ condition; 
or, 
(b) Some of the solution being carried over bodily into the 
collecting-apparatus by too vigorous boiling. 
PROCEDURE. 
The work was begun in August, 1915. There were then prepared 
seven solutions—three of Washington, two of Rutherford-Boltwood 
weak, and two of Rutherford-Boltwood strong. They were made 
up of the same strength. This time the HC1 used in preparing the 
solutions was re-distilled in the Chemistry Building by the writer, 
and tested for radioactive properties. Naturally, there was no 
trace of radioactive property in evidence. 
