The king's ambassador receives no applications from rebels, unless they come to implore his Majesty's mercy. To this the Commissioners rejoined:-- In answer to a letter, which concerns some of the most material interests of humanity, and of the two nations, Great Britain and the United States of America, now at war, we received the enclosed _indecent_ paper, as coming from your Lordship, which we return for your Lordship's more mature consideration. At first the British Government, regarding the Americans as rebels, did not treat their prisoners as prisoners of war, but threatened to try them for high treason. Their sufferings in the English prisons were very great. Mr. David Hartley did much to relieve them, and Franklin transmitted money for the purpose. When a treaty had been formed between France and the States, and France had engaged in the war, and when fortune began to turn in favour of the united armies, the American prisoners received better treatment from the English Government, and exchanges took place freely. In April, 1778, Mr. Hartley visited Franklin at Passy, apparently for the purpose of preventing, if possible, the offensive and defensive alliance between America and France. Very many attempts were made to produce a rupture between the French Government and the American Commissioners, but Franklin insisted that no treaty of peace could be made between England and America in which France was not included. In 1779 the other Commissioners were recalled, and Franklin was made Minister Plenipotentiary to the Court of France. In a letter to Mr. David Hartley, dated February 2, 1780, Franklin showed something of the feelings of the Americans with respect to the English at that time:-- You may have heard that accounts upon oath have been taken in America, by order of Congress, of the British barbarities committed there. It is expected of me to make a school-book of them, and to have thirty-five prints designed here by good artists, and engraved, each expressing one or more of the horrid facts, in order to impress the minds of children and posterity with a deep sense of your bloody and insatiable malice and wickedness. Every kindness I hear of done by an Englishman to an American prisoner makes me resolve not to proceed in the work. While at Passy, Franklin addressed to the _Journal of Paris_ a paper on an economical project for diminishing the cost of light. The proposal was to utilize the sunlight instead of candles, and thereby save to the city of Paris the sum of 96,075,000 livres per annum. His reputation in Paris is shown by the following quotation from a contemporary writer:--