1To Thomas Jefferson from David Rittenhouse, 8 November 1788 (Jefferson Papers)
About two Months ago I received your very valuable present of Books, mentioned in the last letter I had the pleasure to receive from you, for which I am greatly obliged to you. M. Cassini has sent me a Copy of the Observations made at the Royal Observatory at Paris in the Year 1786. I am at a loss to direct to him, will it be convenient for you to return my sincere thanks to him for this...