The very names by which this animal is known to the science which some persons erroneously think must be so hard and dry are poetic. In Aristotle's day it was called the _Nautilus_ or _Nauticus_, "the mariner," and though two thousand two hundred years have passed since the great master wrote, the name still clings to it. As the Pearly Nautilus, a very different animal, also bears that name, Gualtieri perceived the necessity of distinguishing the Paper Nautilus from it, and was followed by Linnaeus, who therefore entitled the genus to which the latter belongs, _Argonauta_, after the ship _Argo_, in which Jason and his companions sailed to Colchis to carry off the "Golden Fleece" suspended there in the temple of Mars, and guarded by brazen-hoofed bulls, whose nostrils breathed out fire and death, and by a watchful dragon that never slept. According to the Greek legend, the _Argo_ was named after its builder Argus, the son of Danaus, and was the first ship that ever was built. Oppian ('Halieutics,' book I.) expresses his opinion that the Nautilus served as a model for the man who first conceived the idea of constructing a ship, and embarking on the waters:-- "Ye Powers! when man first felled the stately trees, And passed to distant shores on wafting seas, Whether some god inspired the wondrous thought, Or chance found out, or careful study sought; If humble guess may probably divine, And trace th' improvement to the first design, Some wight of prying search, who wond'ring stood When softer gales had smoothed the dimpled flood, Observed these careless swimmers floating move, And how each blast the easy sailor drove; Hence took the hint, hence formed th' imperfect draught, And ship-like fish the future seaman taught. Then mortals tried the shelving hull to slope, To raise the mast, and twist the stronger rope, To fix the yards, let fly the crowded sails, Sweep through the curling waves, and court auspicious gales." Pope, too, in his 'Essay on Man' (Ep. 3), adopted the idea in his exhortation-- "Learn of the little Nautilus to sail, Spread the thin oar, and catch the driving gale." Poetry, like the wizard's spell, can make "A nutshell seem a gilded barge, A sheeling seem a palace large," but the equally enchanting wand of science is able by a touch to dispel the illusion, and cause the object to appear in its true proportions. So with the fiction of the "Paper Sailor." I have elsewhere described the affinities of the Nautili and their place in nature, therefore it will only be necessary for me here to allude to these very briefly, to explain the great and essential difference that exists between the two kinds of Nautilus which are popularly regarded as being one and the same animal.