It was natural that he should then come to the most prominent radio-active elements, uranium, thorium, and radium.

" Professor Biggleswade, who had heard vaguely of and rather looked down upon such new-fangled toys as radium and thorium and helium and argonfor the latest astonishing developments in the theory of radio-activity had brought Sir Angus McCurdie his world-wide famesaid somewhat ironically:

One of my assistants was demonstrating a peculiar property of thorium and Deverill seemed interested.

Iridium, osmium, platinum, ruthenium, tantalum, thorium, tungsten, uranium.

So far only radium, thorium, and uranium are generally known.