A notice appears in National Era, looking for participants to "collect, with a view to publication in this country and England, the principle mutilations anidexpurgations of English and American publications by American publishers, booksellers,authors, tract and Sunday School Societies, ec- clesiastical assemblies & committees & c. for the purpose of securing sales in slave states, or the favors of ecclesiastical & political parties & persons in authority, with a discussion of the principles connected with such conduct. It is believed that a full statement of these mutilations and expurgations will astonish the American people and the civilized world."
Grinnell, who was serving as minister at NY Congregational Church, becomes involved as superintendent. In two years of research before going west to Iowa, JB finds 17 hymns that had one or more verses expunged because they contained anti-slavery references.
JB examines historian George Bancroft's History of the United States, as new editions contained justifications of slavery, and original editions were VERY rare. "Pains must have been taken to destroy it," JB surmised. "It was shocking that an American author would expunge his own work at the behest of the Slavepower."
The compilation of research findings, initially JB's job, fell to Tappan because JB left for Iowa. Final project never took on cohesive form, but snippets of research and exposition published in newspapers and journals.