discovery of X-rays he attempted a theoretical explanation for the
first and only time in his life - and got it wrong!

However, this accidental discovery had far-reaching consequences. It
drew attention to the fluorescence of minerals placed in the cathode
tube; this inspired Becquerel to inquire whether naturally fluorescent
substances gave off anything like X-rays, and eventually - yet again by
accident - he came upon certain uranium compounds. These were found to
give off a radiation similar to X-rays, and to give it off naturally
and all the time. Soon afterwards the Curies succeeded in isolating the
element, radium, an element which was found to be undergoing a
continuous natural disintegration. The way was now clear for that long
series of experiments on atomic disintegration which led finally to the
splitting of the nucleus and the construction of the atomic bomb.

*

A typical modern paradox emerges from these results. By restricting his
cognitive powers to a field of experience in which the concept of force
as an objective reality was unthinkable, man has been led on a line of
practical investigation the pursuit of which was bound to land him
amongst the force-activities of the cosmos. For what distinguishes
electric and sub-electric activities from all other forces of physical
nature so far known to science, is that for their operation they have
no need of the resistance offered by space-bound material bodies; they
represent a world of pure dynamics into which spatial limitations do
not enter.

Equally paradoxical is the situation of theoretical thinking in face of
that realm of natural being which practical research has lately