away after the Uranium had been taken from it. This 
refuse was examined, and found to give rays with four 
times the intensity of the rays that Professor Becquerel 
had first noticed. This suggested, if it did not force the 
conclusion, that there was an unknown something in this 
refuse. 
The search for this small quantity of hitherto undis- 
covered material is one of the most remarkable pieces of 
scientific work in verification of a previous train of rea- 
soning. 
Three years before its completion, Professor Curie, of 
the Sorbonne, of Paris, who had made a name for himself 
as a daring and original worker, had won the love and the 
hand of Marie Sklodowski. Together, they worked at 
:his problem through years of depression and even of 
poverty. It was only the courage of Madame Curie that 
sustained and carried through the task. She never lost 
faith; and, as Professor Curie publicly admitted, when he 
was for abandoning the effort, his wife’s striving, dauntless 
spirit refused to even think of defeat. 
The eventual discovery was made by the application 
of methods that mark the utmost refinement achieved by 
science for the measurement of small quantities. 
In brief, and in non-technical language, this work was 
based upon the fact that dry air is not a conductor of 
electricity. By appropriate means, however, it can be 
broken up, so that it will be a conductor. The X-rays 
had demonstrated that they would break up the air through 
which they passed and make it a conductor of electricity. 
The rays that had just been detected as coming from 
Uranium proved that they can convert the air through 
which they passed into a feeble conductor of electricity, 
with more or less of completeness, according to their 
ntensity. 
By ingeniously devised and delicately adjusted elec- 
ical equipment, Madame Curie tested the extent to 
which each of the components into which she separated the 
refuse pitchblende ore she found at the mines, gave rays 
that made air a conductor of electricity. This gave her a