Translation: This passage continues the difficulties of certain terms that appear in the Book of Mormon. We have horses, chariots, and cattle. None of those three items are currently attested in the historical or archaeological records. While it is possible that we are dealing with translation or labeling issues, the precise meaning of the text that would have been on the plates is unknown. It is at least interesting that we continue to see horses and chariots as a paired set (this will happen again in 3 Nephi 21:14) and that they occur in the context of the “substance” that was taken. Neither the horses nor chariots appear in the context of military items, but rather as part of the “substance” that is being removed.
Chronological: The seventeenth year from the sign of the birth of the Savior would be approximately 13 AD.