Samuel Birch remarks on Facsimile 2.
Samuel Birch, "Hypocephalus in the Possession of Sir Henry B. Meuz, Bart," Proceedings of the Society of Biblical Archæology. November, 1883, to May 1884 6 (1884): 37
The following Remarks were made by D. Birch at the meeting held on the 5th June [1883]:—
The object exhibited is a hypocephalus or imperial disk of linen placed under the heads of the mummies in order to maintain the vital warmth. They are either made of laters of linen covered with stucco, or else of papyrus and bronze. (Champollion, "Notice du Musée Charles X," p. 121.)
The linen and plaster ones have figures and inscriptions, generally in black outline on a yellow ground, but in one instance, in yellow outline on a black ground.
These hypocephali appear to have come into use at some period between the XXVIth and XXXth dynasty. None are inscribed with any royal name, so as to fix their date precisely, but the names of the persons for whom they were made, and the coffins of the mummies from which they were taken, seem to point to that period.
The Mormon religion was founded on one of these hypocephali, as will be seen from the publication of Joseph Smith, entitled, "A Pearl of Great Price," in 1851, p. 7, who has figured one of these hypocephali. In the "Archæologia," Vol. XXXVI, p. 163, I have published another, with a full account of the representations and mystical meanings of these disks, and another by M. de Horrack, "Revue Archéologique," 1862, VI, p. 13.