Attempts were made by the other French chemists, about the beginning of the revolution, to associate themselves with Lavoisier, as equally entitled with himself to the merit of the antiphlogistic theory; but Lavoisier himself has disclaimed the partnership. Some years before his death, he had formed the plan of collecting together all his papers relating to the antiphlogistic theory and publishing them in one work; but his death interrupted the project. However, his widow afterwards published the first two volumes of the book, which were complete at the time of his death. In one of these volumes Lavoisier claims for himself the exclusive discovery of the cause of the augmentation of weight which bodies undergo during combustion and calcination. He informs us that a set of experiments, which he made in 1772, upon the different kinds of air which are disengaged in effervescence, and a great number of other chemical operations discovered to him demonstratively the cause of the augmentation of weight which metals experience when exposed to heat. "I was young," says he, "I had newly entered the lists of science, I was desirous of fame, and I thought it necessary to take some steps to secure to myself the property of my discovery. At that time there existed an habitual correspondence between the men of science of France and those of England. There was a kind of rivality between the two nations, which gave importance to new experiments, and which sometimes was the cause that the writers of the one or the other of the nations disputed the discovery with the real author. Consequently, I thought it proper to deposit on the 1st of November, 1772, the following note in the hands of the secretary of the academy. This note was opened on the 1st of May following, and mention of these circumstances marked at the top of the note. It was in the following terms: "About eight days ago I discovered that sulphur in burning, far from losing, augments in weight; that is to say, that from one pound of sulphur much more than one pound of vitriolic acid is obtained, without reckoning the humidity of the air. Phosphorus presents the same phenomenon. This augmentation of weight arises from a great quantity of air, which becomes fixed during the combustion, and which combines with the vapours.