Claude BERNARD (1813-1878). Autograph manuscript signed, Critique expérimentale sur la chaleur animale, [1877]; 132pages oblong large in-8 (approx. 17 x 22 cm.). Precious manuscript of his latest work on animal heat, which remains unfinished and appears to be unpublished. This working manuscript, written in black ink on the front and back of oblong sheets of lined paper, is abundantly crossed out and corrected, with notes and additions in the margins, in pencil or ink. This work is conceived as a series of four communications, probably to the Académie des Sciences, the last two only sketched; it postdates the Leçons sur la chaleur animale, sur les effets de la chaleur et sur la fièvre (Paris Baillière, 1876), to which it refers several times. The first paper, entitled I Topographie calorifique du système sanguin, exists in two versions. - The first version, on 14 sheets (numbered 1-14, plus 11 bis), is heavily corrected; some passages have been taken up and pasted onto a primitive draft; marginal notes indicate developments to be made; sheet 11 bis presents a graph and a drawing of the blood system, in colored inks; on the back of the last sheet, Bernard has sketched a conclusion in pencil, in cursive handwriting on an added sheet (paginated 13-14). - The second, more developed version, on 72 numbered pages, is begun as a clean-up, in turn extensively crossed out and corrected, with new developments; some passages are crossed out entirely, and others are pasted onto a primitive version. This version bears the crossed-out heading: "1ère communication: Topographie calorifique du système circulatoire" (1st paper: Calorific topography of the circulatory system). Divisions appear in the text: I Procédés physiques; II Appareils thermo-électriques (with subdivisions: Galvanomètre; Soudures thermo-électriques; Graduation des soudes et des aiguilles); III Procédés opératoires de vivisection; [IV] Expériences (with 4 colored pencil graphs p.57, 59, 61, 69, and a table p.65). Let's quote the conclusion: "In the final analysis, Lavoisier's idea of the location of a heat source in the lung or elsewhere must be abandoned. Animal heat cannot be localized any more than nutrition, of which it is a direct consequence. Every organ, every tissue, every element of tissue feeds and generates heat. The problem of the origin and mechanism of animal heat production is therefore quite different. To solve it, we no longer have to turn to a special organ or device, but to all the devices, all the organs and all the tissues of the economy, because all of them are the seat of chemical phenomena that accompany nutrition and are the real origins of animal heat. It is this common origin of animal heat in all tissues that we shall try to establish in our next work". The 2nd paper (partly erased in red pencil) is entitled (after correction): Origine générale de la chaleur et sa production dans les différens organes du corps; it runs to 20 pages (pag. 1-18, with 2ff. 11-12). In the margin of the first page, Bernard notes: "Analyse du sang des glandes des muscles et en fonction et en repos". This paper, with numerous erasures and corrections and blanks, is divided into parts (incorrectly numbered): A Production de la chaleur dans les muscles à l'état de contraction (with insertion of a graph in blue and red inks p. 5, and another p.10, on the back of a convocation of the Journal des Savants of March 5, 1877); B Production de la chaleur dans les muscles à l'état de repos; D Production de la chaleur dans les membranes muqueuses et dans les divers tissus; II Production de la chaleur dans les organes nerveux; III Production de la chaleur dans les glandes. The 3rd paper (indicated in red pencil) is entitled: Mechanism of animal heat production; it runs to 7 pages (with erasures and corrections); a marginal note at the top reads: "Papers 3 and 4 can be combined into one". The 4th paper (indicated in red pencil) is entitled: Influence du système nerveux sur la chaleur animale. It runs to 4 pages in cursive handwriting; on the last page, a drawing of test tubes. Enclosed are 3 envelopes from Imprimerie Émile Martinet, with autographed titles.