It must therefore be admitted that an atom of radium, in disaggregating itself, liberates 30,000 times more energy than a molecule of hydrogen when the latter combines with an atom of oxygen to form a molecule of water.
We may ask ourselves how the atomic edifice of the active body can be constructed, to contain so great a provision of energy.

We will remark that such a question might be asked concerning cases known from the most remote antiquity, like that of the chemical systems, without any satisfactory answer ever being given.

This failure surprises no one, for we get used to everything--even to defeat.
When we come to deal with a new problem we have really no right to show ourselves more exacting; yet there are found persons who refuse to admit the hypothesis of the atomic disaggregation of radium because they cannot have set before them a detailed plan of that complex whole known to us as an atom.
The most natural idea is perhaps the one suggested by comparison with those astronomical phenomena where our observation most readily allows us to comprehend the laws of motion.

It corresponds likewise to the tendency ever present in the mind of man, to compare the infinitely small with the infinitely great.

The atom may be regarded as a sort of solar system in which electrons in considerable numbers gravitate round the sun formed by the positive ion.