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    President Jefferson thanks a correspondent for his "communication on the theory of Magnetism"

    Thomas Jefferson Autograph Letter Signed and Free Franked as president. Four integral sheets with Jefferson's letter on the first page, 8" x 10", Washington, March 8, 1805. In this letter, President Jefferson asks Caesar Rodney to deliver a message to Joseph Copes, which includes thanks "for his communication on the theory of Magnetism." The letter reads in full:

    "Th:Jefferson presents his salutations to his friend Mr Rodney and not knowing by what post office a letter will find Mr. Copes, he asks the favor of Mr Rodney to be the bearer of his thanks to Mr Copes for his communication on the theory of Magnetism & his apology for not addressing them directly to him. he is sure also that Mr Rodney can testify to him that unremitting attentions requisite to those matters which duty will not permit him to neglect, render it impossible for him to suffer himself to be drawn off by philosophical subjects, altho' infinitely more pleasing to his mind. he is now hurrying to get through his business in order to make a short visit to his family.
    Washington Mar 8.05."

    On the address panel, Jefferson has written "free Th:Jefferson Pr. U.S. / Caesar A. Rodney esq. / Wilmington [Delaware]." Later penciled annotations occur to the left of the address. Some paper loss above Jefferson's frank resulting from the original opening of the seal, but with no loss of text. Remnants of the seal still exist below the address. Postmarked "Washn. City March 8."

    Earlier on February 15, Joseph Copes, a resident of Sussex County, Delaware, had sent a three-page manuscript on magnetism to President Jefferson. That manuscript began, "To Thomas Jefferson esquire, President of the United States, the friend of science, and the patron of Liberty; his obedient fellow citizen presumes to present this Theory of Magnetism." Even though Copes' February manuscript was addressed from "Broad Creek, Sussex County, Delaware," Jefferson seems uncertain of an address for Mr. Copes (or more specifically, "by what post office a letter will find Mr. Copes"). So, he asks Caesar A. Rodney, who was home in Wilmington, to deliver his message. Two days earlier, Rodney had ended his first term as Delaware's representative in Congress, defeated back in November by the Federalist James Bayard. Jefferson had encouraged Rodney, a political ally, to run for the position earlier in 1803. Later in 1807, President Jefferson would appoint Rodney the U.S. Attorney General.

    In the top left corner of the letter are later penciled notations. Hinged to the front page below Jefferson's text is a piece of paper (5" x 3") written in German identifying the letter.

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    April, 2012
    11th-12th Wednesday-Thursday
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