Nephi's description of the contents of the large plates here gives us some idea of what was on the 116 pages of manuscript that Martin Harris lost (1 Nephi thru Words of Mormon):
1. The record of my father
2. Our journeyings in the wilderness
3. The prophecies of my father
4. Also many of mine own prophecies
According to S. Kent Brown, this verse (1 Nephi 19:1) is intended to describe some of the contents of Nephi's large plates, yet in fact it also describes what is included on the small plates. To illustrate, (a) "the record of my father" corresponds roughly to 1 Nephi 1-10; (b) the "journeyings in the wilderness" appears in 1 Nephi 16-18; and (c) the "prophecies of my father" would include 2 Nephi 1-3 and possibly 1 Nephi 10. [S. Kent Brown, "Nephi's Use of Lehi's Record," in Rediscovering the Book of Mormon, F.A.R.M.S., p. 6]
1 Nephi 19:2 I knew not at the time when I made them that I should be commanded of the Lord to make these plates ([Illustration]): Nephi with the Plates [Paul Mann, Verse Markers, Book of Mormon, Vol. 1, p. 4]
“And Upon the Plates Which I Made I Did Engraven the Record of My Father”
In the preface to the 1830 edition of the Book of Mormon, Joseph Smith wrote that the lost 116 pages included his translation of "[1] the Book of Lehi, which was an account abridged from [2] the plates of Lehi, by the hand of Mormon." However, in Doctrine and Covenants 10:44, the Lord told Joseph that the lost pages contained "an abridgment of [3] the account of Nephi."
According to David Sloan, some critics have argued that these statements are contradictory and therefore somehow provide evidence that Joseph Smith was not a prophet. However, a more careful reading of the Book of Mormon demonstrates that this criticism is invalid.
The Account of Nephi (#3): The description of the lost pages as "an abridgment of the account of Nephi" is clearly accurate. This phase acknowledges Nephi as the principal author and copyist of this portion of the large plates, as well as the maker of those plates. Nephi wrote that he made his large plates so that he could "engraven upon them the record of [his] people. This account was abridged by Mormon and 116 pages of it were lost.
The Plates of Lehi (#2): At first, the reference to "the plates of Lehi" appears to be in error. However, although he may not have personally engraved his record upon Nephi's large plates, Lehi was in a very real sense the first author of those plates. Nephi gave the following description of the contents of the large plates: "And upon the plates which I made I did engraven the record of my father . . ." (1 Nephi 19:1) The large plates apparently contained the full record of Lehi. Nephi probably copied his father's record onto the large plates of Nephi. If the large plates of Nephi began with Lehi's record, this portion of the large plates could accurately be called the plates of Lehi. Such a practice and terminology is confirmed by Jacob who wrote: "These plates [the portion of the small plates of Nephi on which he was recording] are called the plates of Jacob, and they were made by the hand of Nephi" (Jacob 3:14).
The Book of Lehi (#1): Although Nephi made the large plates of Nephi and wrote on them, the portion of the large plates upon which he copied the record of Lehi was apparently termed "the plates of Lehi." Thus Mormon's abridgment of those plates could be described as an account abridged from the plates of Lehi. According to the preface to the 1830 edition of the Book of Mormon, Mormon apparently gave the title "the Book of Lehi" to this abridgment of the plates of Lehi. This action is consistent with Mormon's practice throughout his abridgment of the large plates, in which he frequently grouped multiple authors together in a single book and then named the book after the first author.
But one might ask, "How do you account for the fact that Lehi died well before the time of Benjamin and Mosiah2, which is where Joseph Smith says the 116 pages reached to?" According to Sloan, we can find an example in the book of Helaman. Although the death of Helaman is recorded near the beginning of the book of Helaman (see Helaman 3:37), Helaman's sons Nephi and Lehi were therefore the source of the majority of Mormon's abridgment, yet the book still bears Helaman's name.
In conclusion, the three terms Book of Lehi, plates of Lehi, and account of Nephi are distinct phrases with distinct meanings. [David E. Sloan, "The Book of Lehi and the Plates of Lehi," in Pressing Forward with the Book of Mormon, F.A.R.M.S., 1999, pp. 59-61; see also Journal of Book of Mormon Studies, 6/2 (1997): pp. 269-272]
Note* In the superscription to the book of 1 Nephi we find a fourth term: "[4] An account of Lehi . . ." Yet at the end of the same superscription we also find the following: "This is according to the account of Nephi; or in other words, I, Nephi, wrote this record." [Alan C. Miner, Personal Notes] [See the commentary on 1 Nephi:Superscription; Jacob 3:14]