I received a few days since from my father, the enclosed pamphlet, with directions, after availing myself of the opportunity of perusing it, to return it to you, to whose kindness he was indebted for the loan of it.

I have found in it no material fact, with which I had not been before acquainted, unless it be the authentication by his own narrative of the author’s treachery to his Master; and of that time-serving obsequiousness to the Bourbons, which his morality as well as his religion has ever found him ready to bestow upon the powers that be.

The Abbé de Pradt makes a conspicuous figure in the Dictionnaire des Girouettes, a work in which a multitude of the characters which have made themselves notorious at the various stages of the French Revolution by the versatility of their principles and talents, are displayed in all the colours of the Iris with which they have decorated themselves. Napoleon who had formed a just estimate of his character, employed him in negotiations, where his ecclesiastical profession would contribute together with the vivacity of his wit, the suppleness of his address, and the unprincipled looseness of his morals, to ensure success, and to invest him with an imposing dignity in the eyes of the pious Catholics with whom he employed him to treat, had made him Archbishop of Mechlin—So long as Napoleon, was the spoilt child of Victory, his Archbishop was ready for all his work; whether at Bayonne, at Dresden or at Warsaw—Talleyrand, the ex bishop might have scruples when Napoleon was at the summit of his Fortune; but De Pradt the Archbishop had none till the hero was so far down in his descent as to lead the prelate’s sagacity to the conclusion, that he was never to rise again—He saw that the Counter Revolution, would remove him from his archiepiscopal see, and it behoved him by an early prostration to the Bourbons, to assume the appearance and claim the merit of having anticipated their good fortune by his devotion—He took care therefore to be among the foremost to bow the knee to them upon their reappearance, and now affects to have been the very fly upon the wheel at the Restoration—They have known however how to appretiate him at his real worth, and have left him to make his future way in the world as a political pamphleteer. He writes for the booksellers, and has had the sagacity to perceive the most profitable topic upon which he can publish. Besides this pamphlet, and another upon the affair at Bayonne, and a third upon his own Embassy to Warsaw, he has been vehemently suspected of being the author of the Manuscript from St Helena, a book professing to be from Napoleon himself, but now generally considered as a forgery—It is possible, that this suspicion may be not well founded, but its mere existence shews the equivocal character of the Abbe’s reputation.

He says it was at his instance that the Emperor Alexander in his declaration for himself and his allies, upon entering Paris, after announcing that he would never again treat with Napoleon, added “nor with any of his family.”—This was doubtless an ingenious stroke of address in the Archbishop to ingratiate himself with the Bourbons, but it was superfluous, and worse than useless, as part of the Declaration of the allies; for they would never the more have treated with Napoleon’s family or any part of it, had that passage been omitted, and considering that the Empress Maria Louisa’s father, who had made her a member of Napoleon’s family, was a party to the declaration, it would have been more decent to have spared her the insult and humiliation which it must necessarily cast upon her

But enough of the Abbe de Pradt, whom I ought in justice to thank for the opportunity now afforded me of recalling myself to your recollection, and of assuring you of the respect and veneration which I entertain for your character—I have besides a selfish motive, though connected with the public service, for addressing you at this time—The Senate of the United States, have thought proper to assign, to the Secretary of State, the same task which the House of Representatives in the year 1790 required of you, and which was then so faithfully and ably performed—A Report upon Weights and Measures—The Resolution of the Senate is indeed more extensive than that upon which your Report was formed; as it requires an account of what has been done by foreign nations for establishing uniformity in weights and measures.—And a statement of the regulations and standards as established in the several States of this Union—Together with such propositions as may be proper to be adopted, in the United States.

This last of course is merely matter of individual opinion, and I find in your Report an alternative of two plans, one importing great, and the other smaller deviations from the existing state of things, presented to the Consideration of the House, for their own determination, an example, which I shall certainly deem it my duty to follow.

The great deviation which I have it in contemplation to propose, is an implicit adoption of the new French Metrological system, as already established in France—My motives for taking it as it stands are—1. Because it presents not only the best and most perfect system that ever has been attempted to be carried into execution, but one in itself so good that probably the subject is not susceptible of any material improvement upon it, and certainly no system constructed upon other principles could be made preferable to it—2. Because the work is already done—Done at immense expence and by the labours of many of the most ingenious and profoundest men of the age—3. Because the adoption of it would extend the principle of uniformity to the intercourse between different Nations, and ultimately might lead to the adoption of it, by all the commercial Nations—We have now only the weights and Measures of England with all their varieties and Confusions—We should then have a system not only uniform in itself, but uniform with that of France—The men who understand the most of the Subject in England, strongly incline to the adoption of the French System. The late Lord Stanhope was particularly known to favour it. Should we set them the example, they would probably fall in with it; perhaps at no distant day—Yet when I look at the other side of the question, and observe the obstacles and resistances of every kind, which stand in the way, and make the practicability of so great a change questionable, I shall have some hesitation even in disclosing the opinion that I entertain—I shall feel myself particularly obligated to you, if your leisure and convenience will permit, to be favoured with your ideas on the subject, and with the loan of any work or Treatise upon Metrology which you may possess—I have made some unsuccessful search for the Reports of the Committees of the House of Commons in 1758 and 1759. and for the Report of Mechain and Delambre, on their measurement of the Arc of the Meridian between Dunkirk and Barcelona. I have as yet been unable to procure them either in England or France—I have found in the Library which was yours, a valuable collection of Tracts on the general subject, which I have no doubt will prove useful to me.