Harriet Martineau's account of her childish terror caused by seeing some prismatic colours dancing on the wall of a vacant room she was entering--'imps' that had no worse origin than a tremulous candelabrum, but which haunted her nerves through life--is an experience which may be traced in the haunted childhood of every nation. There are other phenomena besides these prismatic colours, which have had an evil name in popular superstition, despite their beauty. Strange it might seem to a Buddhist that yon exquisite tree with its blood-red buds should be called the Judas-tree, as to us that the graceful swan which might be the natural emblem of purity should be associated with witchcraft! But the student of mythology will at every moment be impressed by the fact that myths oftener represent a primitive science than mere fancies and conceits. The sinuous neck of the swan, its passionate jealousy, and the uncanny whistle, or else dumbness, found where, from so snowy an outside, melody might have been looked for, may have made this animal the type of a double nature. The treacherous brilliants of the serpent, or honey protected by stings, or the bright blossoms of poisons, would have trained the instinct which apprehends evil under the apparition of beauty. This, as we shall have occasion to see, has had a controlling influence upon the ethical constitution of our nature. But it is at present necessary to observe that the primitive science generally reversed the induction of our later philosophy; for where an evil or pain was discovered in anything, it concluded that such was its raison d'être, and its attractive qualities were simply a demon's treacherous bait. However, here are the first stimulants to self-control in the lessons that taught distrust of appearances.