Paris, De Feugueray, 1820. Uncut in orig. printed wrappers, partly unopened. In: ""Annales de Chimie et de Physique, Par Gay-Lussac et Arago."", Tome XIII - Avril 1820. The whole issue: pp. 337-448. Laplace's paper: pp. 410-417. Fourier's paper:pp. 418-438.
Both papers discusses the cooling of the earth in order to calculate the age of the earth.