Louis GAYANT (died 1673), surgeon and anatomist, specialist in blood circulation; he was the first in France to perform a blood transfusion between dogs in 1667. Autograph manuscript signed, 6 pp. ½ in-4. Undated (circa 1667). Precious manuscript reporting on his experiments with blood transfusion. "Account of the research carried out last year [...] on anatomy". "Firstly, there was talk of the transfusion of blood from one animal into another, which was practised in England. At the same time, I had a number of blowtorches made in different ways to carry out experiments, because from the outset I thought it was possible; we carried them out on dogs by passing the blood from the carotid artery into the jugular vein or the crural vein, weighing the dogs to find out precisely how much blood they had given and received, Some of them died, and we did not see the beneficial results that the advocates of this operation promise themselves, which leads us to believe that it is useless for curing illnesses, either because of the difficulty of performing it on humans, or because of the danger of giving blood which, not being natural to the person receiving it, cannot bring relief [?] ". He also describes experiments on the brain.