WASHINGTON, February 15, 1808. SIR,--I have duly received your letter of the 8th instant, on the subject of the stone in your possession, supposed meteoric. Its descent from the atmosphere presents so much difficulty as to require careful examination. But I do not know that the most effectual examination could be made by the members of the National Legislature, to whom you have thought of exhibiting it. Some fragments of these stones have been already handed about among them. But those most highly qualified for acting in _their_ stations, are not necessarily supposed most familiar with subjects of natural history; and such of them as have that familiarity, are not in situations here to make the investigation. I should think that an inquiry by some one of our scientific societies, as the Philosophical Society of Philadelphia for example, would be most likely to be directed with such caution and knowledge of the subject, as would inspire a general confidence. We certainly are not to deny whatever we cannot account for. A thousand phenomena present themselves daily which we cannot explain, but where facts are suggested, bearing no analogy with the laws of nature as yet known to us, their verity needs proofs proportioned to their difficulty. A cautious mind will weigh well the opposition of the phenomenon to everything hitherto observed, the strength of the testimony by which it is supported, and the errors and misconceptions to which even our senses are liable. It may be very difficult to explain how the stone you possess came into the position in which it was found. But is it easier to explain how it got into the clouds from whence it is supposed to have fallen? The actual fact however is the thing to be established, and this I hope will be done by those whose situations and qualifications enable them to do it. I salute you with respect. TO MR. ANTHONY G. BETTAY. WASHINGTON, February 18, 1808. SIR,--I have duly received your letter of January 27th. With respect to the silver mine on the river Platte, 1,700 miles from St. Louis, I will observe that in the present state of things between us and Spain, we could not propose to make an establishment at that distance from all support. It is interesting however that the knowledge of its position should be preserved, which can be done either by confiding it to the government, who will certainly never make use of it without an honorable compensation for the discovery to yourself or your representatives, or by placing it wherever you think it safest.