NUCLEAR ENERGY AND THE HYDROGEN BOMB^ 
r L. Hughes. Professor of Physics, Washington University) 
A satisfactory unde 
the uranium bomb and how it may possibly be released in the hydrogen 
bomb calls for a survey of many apparently unrelated developments in 
science during the last half century. Our success in releasmg nuclear 
energy at will, is, to my mind, perhaps the most outstanding illustra- 
tion of how new and important discoveries are made by not going after 
them. They are often made as a result of scientists following their in- 
dividual curiosity as to this or that phenomenon without the slightest 
idea of what will be the end result. 
I shall first briefly enumerate the various significant dates in the 
history of the backgroimd to the atomic bomb. 
In 1897 Madame Curie isolated radium and it was found later to have 
properties of a very peculiar kind. Unlike all other elements which 
seemed to be eternal and everlasting, radium transmutes itself at a de- 
finite rate into a different element, radon. The study of this and rela- 
ted phenomena opened up the fascinating field of radioactivity, or natu- 
ral transmutation. The leader in this field was Rutherford. 
In 1906 Einstein published his theory of relativity. As a side pro- 
the startline prediction that 
rgy 
ounce 
appear in its place and vice -versa. To be specific, i 
ter of any kind could be made to disappear entirely, then 700,000,000 
kwh of energy would appear in its place. This is nearly as much as the 
power plant at Keokuk puts out in a year. Alternatively, it is roughly 
equal to the total power output of the Union Electric Company for two 
months. 
Einstein's prediction remained vmverified until the 1930' s when it 
was shown in certain experiments in which a minute fraction of the ■ 
mass involved disappeared, that the right amount of energy appeared ir 
its place. 
in artificial transmutation. 
particles from raHinm ha 
through the first successful experiment 
rtnmhardin? nitroeen atoms with alpha 
irom radium, he succeeded in creating oxygen arom&. 
In the late 1920' s E.O. Lawrence and others devised particle accel- 
erators, such as the cyclotron, to accelerate suitable particles, such as 
protons and alpha particles, to repeat and extend Rutherford's trans- 
mutation experiments. The advantage of the particle accelerator was 
"^t it could provide ever so many more bombarding particles thanwer< 
available to Rutherford who used radium as a source of alpha particles 
An address at the Annual Dinner of the Academy of Science of St 
^°uis March 1. 1950. 
121 
