The first official US pharmacopoeia. Spalding began campaigning for a national pharmacopeia in 1815. His efforts finally bore fruit in a national convention that met in 1820 and adopted a pharmacopeia based mainly on the Pharmacopoeia of the Massachusetts Medical Society (1808). Spalding chaired the Committee of Publication for the  national pharmacopoeia. The title page of the first edition bore the date "Dec. 1820" Digital facsimile from the Internet Archive at this link.