10. In the same volume of the Memoirs of the Academy, appeared his paper "On the Ash employed by the Saltpetre-makers of Paris, and on its use in the Manufacture of Saltpetre." This is a curious and valuable paper; but not sufficiently important to induce me to give an abstract of it here. 11. In the Memoirs of the Academy, for 1777, appeared an elaborate paper, by Lavoisier, "On the Combination of the matter of Fire, with Evaporable Fluids, and the Formation of Elastic aeriform Fluids." In this paper he adopts precisely the same theory as Dr. Black had long before established. It is remarkable that the name of Dr. Black never occurs in the whole paper, though we have seen that Lavoisier had become acquainted with the doctrine of latent heat, at least as early as the year 1772, as he mentioned the circumstance in a short paper inserted that year in the Journal de Physique, and previously read to the academy. 12. In the same volume of the Memoirs of the Academy, we have a paper entitled "Experiments made by Order of the Academy, on the Cold of the year 1775, by Messrs. Bezout, Lavoisier, and Vandermond." It is sufficiently known that the beginning of the year 1776 was distinguished in most parts of Europe by the weather. The object of this paper, however, is rather to determine the accuracy of the different thermometers at that time used in France, than to record the lowest temperature which had been observed. It has some resemblance to a paper drawn up about the same time by Mr. Cavendish, and published in the Philosophical Transactions. 13. In the Memoirs of the Academy, for 1778, appeared a paper entitled "Analysis of the Waters of the Lake Asphaltes, by Messrs. Macquer, Lavoisier, and Sage." This water is known to be saturated with _salt_. It is needless to state the result of the analysis contained in this paper, because it is quite inaccurate. Chemical analysis had not at that time made sufficient progress to enable chemists to analyze mineral waters with precision. The observation of Lavoisier and Guettard, which appeared at the same time, on a species of steatite, which is converted by the fire into a fine biscuit of porcelain, and on two coal-mines, the one in Franche-Comté, the other in Alsace, do not require to be particularly noticed.