[George Q. Cannon]
... In speaking of the translating he [David Whitmer] said that Joseph had the stone in a hat from which all light was excluded. In the stone the characters appeared and under that the translation in English and they remained until the scribe had copied it correctly. If he had made a mistake the words still remained and were not replaced by any other. In describing the visit of the angel he said that it was shortly before the completion of the translation when there were but few pages left. He was plowing when Joseph and Oliver came to him and the former told him that he was chosen to be one of the three witnesses to whom the angel would show the plates. He also told him that the Lord had promised to make this manifest and now was the time. They went out and sat upon a log conversing upon the things to be revealed when they were surrounded by a glorious light which overshadowed them. A glorious personage appeared and he showed to them the plates, the sword of Laban, the Directors, the Urim and Thummim and other records. Human language could not, he said, describe heavenly things and that which they saw. The language of the angel was: Blessed is he that believeth and remaineth faithful to the end. He had his hours of darkness and trial and difficulty, but however dark upon other things that [vision] had ever been a bright scene in his mind and he had never wavered in regard to it; he had testified fearlessly always of it, even when his life was threatened. Martin Harris was not with them at the time that he and Oliver saw the angel, but he and Joseph afterwards saw the same, and he thus became a witness also.
George Q. Cannon, Journal, 27 February 1884, LDS Church Archives, Salt Lake City, Utah. 2.
George Q. Cannon, "Topics of the Times," Juvenile Instructor 19 (1 April 1884): 106-7., as cited in Dan Vogel, Early Mormon Documents: David Whitmer Interview With George Q. Cannon]