Holmes' persistence finally began to pay off in 1921, when the speakers at the yearly meeting of the British Association for the Advancement of Science came to a rough consensus that Earth was a few billion years old, and that radiometric dating was credible.
Holmes' udholdenhed begyndte endelig at give resultat i 1921, da talere ved årsmødet i Den britiske forening til videnskabens fremme nåede til bred enighed om, at Jorden var nogle få milliarder år gammel, og at radiometrisk datering var troværdig.