Progress on dating the age of the Earth was slow. Years, even decades went by without any significant advance being made. But science is like that. What is often not realised when the breakthrough finally occurs is that for years previously a few individuals had been diligently working in the background, thinking and writing about the problems, quietly and persistently pursuing their goal. Arthur Holmes was one. Every few years he took it upon himself to write an article summarising the current state of play with regard to the age of the Earth. In simple and lucid language he explained to the scientist and layman alike the history of radioactivity, its application to dating minerals and the age of the Earth, and included any recent developments. Year after year he said much the same thing: Kelvin's arguments were shot down in flames, the ‘hour-glass’ methods were swept aside, and radioactivity emerged victorious. Slowly, bit by bit, this one-man campaign spread the word about the great antiquity of the age of the Earth.

He also continued to build up the database. As early as 1923 a committee had been set up in America for ‘The Measurement of Geologic Time by Atomic Disintegration’, its objectives being to collate and monitor all the dating of rocks being done around the world.