1Thomas Jefferson to Timothy Dwight Porter, 26 March 1820 (Jefferson Papers)
Th: Jefferson returns his thanks to mr Porter for the copy of the constn of the Amer. geolog. soc. which he has had the kindness to send him . the names of it’s officers as subjoined to it are a sufficient pledge to the world of it’s future utility usefulness & celebrity. he salutes the Society & mr Porter with the most respectful considn