In consequence of [Joseph Smith's] vision, and his having the golden plates and refusing to show them, a great persecution arose against the whole family, and he was compelled to remove into Pennsylvania with the plates, where he translated them by means of the Urim and Thummim, (which he obtained with the plates), and the power of God. The manner in which this was done was by looking into the Urim and Thummim, which was placed in a hat to exclude the light, (the plates lying near by covered up), and reading off the translation, which appeared in the stone by the power of God. He was engaged in this business as he had opportunity for about two years and a half. In the winter of 1829 and thirty, the Book of Mormon, which is the translation of part of the plates he obtained, was published. He then showed the plates to my father and my brothers Hyrum and Samuel, who were witnesses to the truth of the book which was translated from them. I was permitted to lift them as they laid in a pillow-case; but not to see them, as it was contrary to the commands he had received. They weighed about sixty pounds according to the best of my judgment.