In _The Builder_ for May 12, 1916, appeared a diagram accompanied by a note from a firm of publishers who stated that they had received the sketch from one of their travellers who was then serving on the Arras front. "He informs us," they state, "that it is not a puzzle, but a plan of the labyrinth under the cathedral. He found the prints in a ruin in the vicinity, a house which appears to have been occupied by a librarian from what he saw among the débris." The sketch in question is of an octagonal pattern resembling that of the St. Quentin labyrinth, and represents the pavement-labyrinth that formerly existed in the now ruined cathedral, not, of course, a system of subterranean passages, as the correspondent evidently inferred. It was about 34-1/2 ft. in diameter and was composed of small blue and yellow squares. The destruction of this labyrinth cannot be debited to the account of the aggressors in the Great War, as it was carried out during the French Revolution. [Illustration: FIG. 53.--Labyrinth in Sens Cathedral. (Gailhabaud.)] [Illustration: Fig. 51. Amiens. Central Plate of Labyrinth. (Gailhabaud)] [Illustration: Fig. 52. Labyrinth in Bayeux Cathedral. (Amé)] A labyrinth of rather striking design (Fig. 54) was formerly in the pavement of the old Abbey of St. Bertin, an edifice which has long been a picturesque ruin, in the lower part of the town of St. Omer. A description of it was first published nearly a century ago by Emmanuel Wallet (or Vallet). Our figure, which accords with his notes, differs slightly from that which has usually accompanied the references of subsequent writers--many of whom, by the way, erroneously speak of it as being in the cathedral, which is in the upper part of the town, and at some distance from St. Bertin. Most illustrations of the labyrinth in question show the path as crossing itself at one point, an arrangement which is most unlikely to have been adopted. Wallet based his description on a manuscript which, judging by the watermark in the paper, he attributed to a former English student at the college in the vicinity. [Illustration: FIG. 54.--Labyrinth in Abbey of St. Bertin, St. Omer. (Wallet.)] This labyrinth was apparently destroyed at about the same time as that at Rheims, and for a similar reason. In the cathedral there is no pavement-labyrinth, although it may possibly have possessed one in former times, but beneath the organ, at the west end of the nave, is a curiously engraved slab which is worth mentioning in this connection, for it represents a sort of "chemin de Jérusalem," though not indeed of the usual type. It shows, around a large circle, mountains, rivers, towns, roads, and animals, together with the word IhERVSALEM, whilst the interior of the circle is divided into three horizontal compartments, in each of which are placed various objects indistinguishable through wear. The slab was very much worn when described by Wallet and has possibly been replaced by now.