First edition. Athanase Dupré (1803-1869) was Dean of the Faculty of Sciences of Rennes and a renowned French physicist. His work Théorie mécanique de la chaleur (Mechanical Theory of Heat) is an important contribution to the understanding of thermodynamics and heat in the 19th century, a pivotal period for the development of these concepts. The inclusion of an experimental section, in collaboration with Paul Dupré, highlights the importance of empirical approaches in validating physical theories of the time. This work is part of the debates and advancements that led to the establishment of the laws of thermodynamics.