The favorable Recollection which Your Excellency is so kind to honor me with, in his1 letter of the 25th ulto; is an Object of the greatest Satisfaction to me, I am sorry that the Circumstances deprive me yet of the opportunity to shew actively how much I am, in all Situations, disposed to every exertion, towards deserving the approbation of men, who will be so kind to cast an indulgent Judgement upon me.

The Collection of mathematical Instruments & Books, which I procured for the Survey of the Coast, would not be well appropriated for the use of an University, both on Account of its peculiar Nature, as because allmost every part contains Duplicates; and the Collection of Standard „Weights &„ Measures might likely be usefull only in the possession of the Government.   The Amount paid by me in London & Paris is £3733.10.6½2 sterling.

The philosophical Society of Philadelphia requested last Year the Loan of some of the Instruments, to establish an Observatory, but was refused it; the Intention of Government appears to be: to preserve them in the War Department for future use.

I have taken the Liberty to propose to the President of the United States: to establish a national Observatory in Washington, as Instruments, purposely intended for it, are in the Collection, and I had already in 1816. given in the Treasury Department the Plan of an appropriated Building.

Besides the general Scientific Interest and utility, it could become of direct use to Government, by uniting with it: Instruction in nautical Astronomy and hydrography for the Navy, and making it the Deposit of the Standards of Weights & Measures, both Objects now desirable.

The Establishment of it at the Metropolis, where Representatives of the whole Nation meet every Year, would not only spread Interest for Science in the Country; but might probably serve as an Inducement to the Establishment of a Seminary of Learning at Washington, in that Genius, which appears both generally appropriated, and peculiarly adapted to the wants of this Country: namely for exact and natural Sciences; which would form the necessary nursery of Science, without any reference to religious and political Opinions, which seemes to be apprehended in such an Establishment; and furnish for the use of the Government, and the Country at large, well informed men for those practical branches of these sciences, which are of daily application in the Country, and for which the Success of the Military Academy has certainly already given some Encouragement; this very Establishment might then, with advantage, become peculiarly appropriated only to the branch indicated by its name, the Scholars having passed the theoretical Institution before, the same might then apply to the Instruction for the Navy, &c

But I must not here detain You with the Exposition of my Ideas upon a full System of such concurring Establishments, I have only taken the Liberty to tuch the Subject, as a hint upon my more distant Views in the Establishment of a national Observatory, and to take the Liberty to recomand the Idea in Your patronage, as I have every reason to believe: that if supported by men, who so deservedly command the highest Confidence and Credit, it would find a favorable ear in Congress, in its present friendly Disposition towards the Navy, which would be directly benefited by it, and I know several distinguished members of Congress, desiring very much the Establishment of a national Observatory.

If the Instruments are not used at present, a similar Establishment, made at a later period with the same, would, though good, however by the natural Progress of Science, bear at its very birth the appearance of old, besides that the Amount already laid in the Instruments remains so long unproductif, and liable to suffer deterioration.

I am happy to understand that Mr Lechot gives Satisfaction in his Establishment, as I expected; I will take Informations about a Silversmith; but at present I know of none within the sphere of my Connections.

I pray You will accept kindly the homage of the most sincere attachement, and the most profound Esteem with which I have the honor to be.