Context:
But I have got into a long disquisition on politics, when I only meant to express my sympathy in the state of your health, and to tender you all the affections of public & private hospitality. I should be very happy indeed to see you here. I leave this about the
30thinst., to return about the twenty-fifth of April. If you do not leave Philadelphia before that, a little excursion hither would help your health. I should be much gratified with the possession of a guest I so much esteem, and should claim a right to lodge you, should you make such an excursion.
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http://teachingamericanhistory.org/library/document/letter-to-priestley/