Is the Book of Abraham Papyrus "Missing"?

In 1835, Joseph Smith purchased an ancient Egyptian funerary scroll containing a Document of Breathing Made by Isis, which anciently belonged to a priest named Hor.  Because the fragments from the outer end of the scroll were falling apart, the prophet and his scribes preserved them by pasting them to stiff backing paper.  The interior portion of the scroll was better preserved, and remained intact as a scroll.  The mounted outer fragments have survived, but the intact interior portion was burned in the Great Chicago Fire of 1871.

Handwritten manuscripts from the Kirtland period of LDS Church history seem to indicate that the Book of Abraham was "translated" from one of the extant mounted fragments of this scroll.  But when this fragment is translated Egyptologically, it turns out to have nothing to do with Abraham.  As a result, missing papyrus theorist John Gee has argued that a Book of Abraham may have followed the Document of Breathing on the lost interior portion of the scroll.  He explains, "Both Mormon and non-Mormon eyewitnesses from the nineteenth century agree that it was a 'roll of papyrus from which [Joseph Smith] translated the Book of Abraham,' meaning the 'long roll of manuscript,' and not one of the mounted fragments that eventually ended up in the Metropolitan Museum of Art" (John Gee, “Some Puzzles from the Joseph Smith Papyri,” FARMS Review 20, no. 1 (2008): 119).

Dr. Gee's claim is not accurate.  Consider the following eyewitness accounts, which indicate that both the mounted fragments and the intact portion of the scroll were identified as an Abrahamic record, and in fact the "deciphered" portion of the record was among the fragments:

"[Joseph Smith] then walked to a secretary, on the opposite side of the room, and drew out several frames, covered with glass, under which were numerous fragments of Egyptian papyrus, on which, as usual, a great variety of hieroglyphical characters had been imprinted. . . . There, said he, pointing to a particular character, that is the signature of the patriarch Abraham."
(“A Glance at the Mormons,” The Friend; a Religious and Literary Journal 13, no. 43 [July 25, 1840]: 342–43.)

"Some parchments inscribed with hieroglyphics were then offered us. They were preserved under glass and handled with great respect. 'That is the handwriting of Abraham, the Father of the Faithful,' said the prophet."
(Josiah Quincy, Figures of the Past: From the Leaves of Old Journals, (Boston, Mass.: Roberts Brothers, 1883), 386.)

"From this he drew forth a number of glazed slides, like picture frames, containing sheets of papyrus, with Egyptian inscriptions and hieroglyphics. These had been unrolled from four mummies, which the prophet had purchased at a cost of twenty-four hundred dollars. By some inexplicable mode, as the storekeeper informed me, Mr. Smith had discovered that these sheets contained the writings of Abraham, written with his own hand while in Egypt."
(Henry Caswall, The City of the Mormons, or Three Days at Nauvoo, in 1842, 2nd rev. and enl. ed. [London: J.G.F. & J. Rivington, 1843], 22.)

"[Lucy Mack Smith] produced a black looking roll (which she told us was papyrus) found on the breast of the King, part of which the prophet had unrolled and read; and she had pasted the deciphered sheets on the leaves of a book which she showed us."
(M. to Friends’ Weekly Intelligencer, September 1846, in Friends’ Weekly Intelligencer 3, no. 27 [October 3, 1846]: 211-12.)

Our current English text of the Book of Abraham was translated from pJS XI, the "instructions" column of the Document of Breathing. This needn't threaten faith or membership in the Church, but it may require a change of paradigms in the way Mormons think about translation and prophethood. Such changes can be frightening and traumatic at first, but ultimately I think people will find they are also beneficial. Some may even find their faith deepened by the experience. One example of such a paradigm change in action is Karl C. Sandberg, "Knowing Brother Joseph Again: The Book of Abraham, and Joseph Smith as Translator," Dialogue 22 (Winter 1989): 17-38. Another I recommend is Jason Monson's Mormon pluralism.