In one of their experiments, as shown in
Ernst Rutherford (1871 –
1937)  New Zealand born,
British physicist who did
pioneering 
work 
on
radioactive radiation He
discovered alpha-rays and
beta-rays Along 
with
Federick Soddy, he created
the modern theory of
radioactivity He studied
the ‘emanation’ of thorium
and discovered a new noble
gas, an isotope of radon,
now known as thoron