Jesse Townsend wrote that Joseph and Oliver Cowdery wrote a pretended translation of the BOM.
Jesse Townsend to Phines Stiles, December 24, 1833, printed by the Christian Tract Society as “A Minister’s Opinion of Joseph Smith, Jr." (1968), M209 T748m, Church History Library
Joe visited a visionary fanatic by the name of Martin Harris, and told him he had received some golden plates of ancient records from the Lord, with a “revelation” to call on him for fifty dollars to enable him to go to Pennsylvania and translate the contents of the plates. . . . Some other men, having a great dislike to labor, joined Joe in his deceptions, among whom was a sort of schoolmaster named Cowdery, who assisted him in writing or transcribing the “Book of Mormon,” as a pretended translation of the golden plates which he affirmed he had been directed by the Spirit of the Lord to dig from the earth. This was all done in the most secret manner. At the same time it was assumed to the uninitiated that it would be “immediate death” for any except the translators to see the plates.