Here's the vision that Heber C. Kimball and others saw the night of 22 September 1827. It's no wonder that Heber C. Kimball and John Young (Brigham Young's father) accepted the gospel when they finally heard it. The Kimballs didn't meet the missionaries until 1831. This is taken from: The Life of Heber C. Kimball, written by Orson F. Whitney, chapter 3.
It was the eventful night of September 22, 1827. Says Heber C. Kimball:
"I had retired to bed, when John P. Greene, who was living within a hundred steps of my house, came and waked me up, calling upon me to come out and behold the scenery in the heavens. I woke up and called my wife and Sister Fanny Young (sister to Brigham Young), who was living with us, and went out-of-doors.
It was one of the most beautiful starlight nights, so clear that we could see to pick up a pin. We looked to the eastern horizon, and beheld a white smoke arise toward the heavens; as it ascended it formed itself into a belt, and made a noise like the sound of a mighty wind, and continued southwest, forming a regular bow dipping in the western horizon. After the bow had formed, it began to widen out and grow clear and transparent, of a bluish cast; it grew wide enough to contain twelve men abreast.
In this bow and army moved, commencing from the east and marching to the west; they continued marching until they reached the western horizon. They moved in platoons, and walked so close that the rear ranks trod in the steps of their file leaders, until the whole bow was literally crowded with soldiers. We could distinctly see the muskets, bayonets and knapsacks of the men, who wore caps and feathers like those used by the American soldiers in the last war with Britain; and also saw their officers with their swords and equipage, and the clashing and jingling of their implements of war, and could discover the forms and features of the men. The most profound order existed throughout the entire army; when the foremost man stepped, every man stepped at the same time; I could hear the steps. When the front rank reached the western horizon a battle ensued, as we could distinctly hear the report of arms and the rush.
No man could judge of my feelings when I beheld that army of men, as plainly as ever I saw armies of men in the flesh; it seemed as though every hair of my head was alive. This scenery we gazed upon for hours, until it began to disappear.
After I became acquainted with Mormonisim, I learned that this took place the same evening that Joseph Smith received the records of the Book of Mormon from the angel Moroni, who had held those records in his possession.
John Young, Sen., and John P. Greene's wife, Rhoda, were also witnesses.
My wife, being frightened at what she saw, said, 'Father Young, what does all this mean?'
'Why, it's one of the signs of the coming of the Son of Man,' he replied in a lively, pleased manner.
The next night similar scenery was beheld in the west by the neighbors, representing armies of men who were engaged in battle.