The Atlantean Museum was a museum of natural history established in Hanover, Atlantis early in the 19th century by a donation by a Briton. While it could not compare to the British Museum, it did have an excellent collection of Atlantean floral and fauna and very good specimens of Terranovan wildlife.
The honker specimens were especially impressive. In addition to skeletons and eggshells, hides with feathers still attached were displayed in lifelike appearance through clever taxidermy. In the early 1830s John Audubon visited the Museum to closely examine these specimens in preparation to paint them. This allowed him to correctly identify the honkers he found during his famous 1843 excursion as Agile Honkers. A generation later, Doctor James Walton was quite taken with the display and encouraged his companion Athelstan Helms to come, take a look.
The two were awaiting contact from The Preacher after informing Rector Henry Praeger of their interest in speaking with him. Helms was not interested in seeing the Museum until Walton mentioned the extensive botanical displays, especially the various poisonous plants. Helms reflected on his previous interest in certain plants that produce noxious alkaloids and agreed to go the next day. When the two came to the exhibit of plants, Walton noticed a folded piece of foolscap which had written on it "Be on the 4:27 train to Thetford tomorrow afternoon". Helms was especially impressed by The Preacher's powers of deduction and his ability to predict Helms' visit and which exhibit he would seek. This being so, he declared his intention to be on that train.