Marseilles, 15 Dec. 1788. Is fully aware of the honor done him in being entrusted to further TJ’s beneficial views on the commercial relations between Marseilles and the United States; will zealously endeavor to learn by experiment how much potash can be used supplementally with soda and other materials in the manufacture of soap, glass, china, and dyes, and at what price the manufacturers could buy to make its use practical. The amount of potash TJ has had sent to Marseilles (“cinq Barriques”) will enable Audibert to make these experiments; he will proceed with exactness and will render a detailed report of his findings in order that the U.S. merchants engaged in this trade may regulate their operations with full knowledge of the situation. Expresses his appreciation of the confidence placed in him; will always be glad to assist in enterprises relating to Marseilles.