It was supposed by the Norway fishermen to have a great objection to castor, with which they provided themselves when going out to sea, shutting it up in a hole in the stern, and throwing a little overboard when apprehensive of meeting the sea-snake. The Faroe fisherman had the same idea with reference to the Tvold whale, which was supposed to have a great aversion to castor and to shavings of juniper wood. Olaus Magnus, in his _Histor. Septentrion_, chap. xxvii., writing not from personal observation but from the relations of others, speaks of it as being two hundred feet in length and twenty feet round, having a mane two feet long, being covered with scales, having fiery eyes, disturbing ships, and raising itself up like a mast, and sometimes snapping some of the men from the deck. Aldrovandus, quoting Olaus Magnus, says that about Norway there occasionally appears a serpent reaching to one hundred or two hundred feet in length, dangerous to ships in calm weather, as it sometimes snatches a man from the ship. It is said that merchant ships are involved by it and sunk. Olaus Magnus also figures another serpent, which is said to inhabit the Baltic or Swedish Sea; it is from thirty to forty feet in length, and will not hurt anyone unless provoked. [Illustration: FIG. 67.--SEA-SERPENT ATTACKING A VESSEL. (_From Olaus Magnus._)] Arndt. Bernsen, in his account of the fertility of Denmark and Norway, says that the sea-snake, as well as the Tvold whale, often sinks both men and boats; and Pontoppidan was informed by the North traders that the sea-snake has frequently raised itself up and thrown itself across a boat, and even across a vessel of some hundred tons burthen, and by its weight sunk it to the bottom; and that they would sometimes raise their frightful heads and snap a man out of a boat; but this Pontoppidan does not vouch for, and, indeed, says that if anything, however light, be thrown at and touch them they generally plunge into the water or take another course. Hans (afterwards Bishop) Egede, in his _Full and Particular Relation of my Voyage to Greenland, as a Missionary, in the year 1734_, figures and describes a sea-monster which showed itself on his passage. He says: "On the 6th of July 1734, when off the south coast of Greenland, a sea-monster appeared to us, whose head, when raised, was on a level with our main-top. Its snout was long and sharp, and it blew water almost like a whale; it had large broad paws; its body was covered with scales; its skin was rough and uneven; in other respects it was as a serpent; and when it dived, its tail, which was raised in the air, appeared to be a whole ship's length from its body."