Sir,--I am thankful for the trouble which yourself and Dr. Hutchinson have taken, and are still willing to take, on the subject of Mr. Isaacs' discovery. However his method may turn out, this advantage will certainly result from it, that having drawn the public attention to the subject, it may be made the occasion of disseminating among the masters of vessels a knowledge of the fact, that fresh water may be obtained from salt water by a common distillation, and in abundance. Though Lind's, Irvine's, and McQueer's experiments should suffice to satisfy them of this, yet it may fix their faith more firmly, if we can say to them that we have tried these experiments ourselves, and can vouch for their effect. If Mr. Isaacs can increase that effect, so much the better; it will be a new flower in the American wreath. He is poor, and complains that his delay here is very distressing to him. Therefore, I propose to-morrow for the experiment, and will ask the favor of you to fix any hour that may best suit the convenience of Dr. Hutchinson and yourself, from five in the morning to twelve at night, all being equal to me. Only be good as to notify it in time for me to give notice to Mr. Isaacs. Will it not save time, if the great still can be set agoing at the same time with the small ones? He protests against any unfavorable conclusions from a small experiment, because never having tried his method in a small way, he does not know how to proportion his mixture. I am, with great esteem, Sir, your most obedient humble servant. TO HIS EXCELLENCY GOVERNOR MARTIN. Philadelphia, March 26, 1791.