John Tyndall, born in Leighlinbridge (County Carlow, Ireland), demonstrates experimentally in 1859 at the Royal Institution in London that CO₂ and water vapor absorb infrared radiation while nitrogen and oxygen do not. He publishes his results in Philosophical Magazine (1861). He is the first to quantitatively measure different gases' capacity to retain heat, establishing the experimental basis of the greenhouse effect. Eunice Newton Foote (US) had observed the phenomenon in 1856 without Tyndall's institutional backing or instrumentation; both contributions are now recognized as complementary. Tyndall's name barely appears in contemporary public climate debate despite being the experimental basis of all climatology.