Congress having referred to me the petition of Jacob Isaacs setting forth his possession of a secret for facilitating the separation of sea-water from it’s salt, it becomes necessary for me to know exactly the advances which have been already made towards obtaining that desideratum. I have reason to believe no body has carried them further than Dr. Lind. I possess his book on the diseases of warm climates, in which he has stated some general account of his method of distilling sea-water, and refers for more precise information to a pamphlet of his on the health and preservation of seamen. This pamphlet I cannot get. Besides this I understand there was another publication of his the object of which was to criticise Irving’s method of distilling sea-water, and to prove his own right to what was useful in that. I am told you possess this, and perhaps you may possess also the former pamphlet. If you do, and will be so good as to send me both or either by post, they shall be most sacredly returned. They will come perfectly safe by the post. Your favor herein will much oblige Sir Your most obedt. humble servt,