Vickipedia

CHEMICAL TOYS, which in the course of recent years have been brought prominently before the public, deserve a brief notice. ‘Pharaoh’s Serpents,’ which have been already described in the article SULPHOCYANOGEN, are highly poisonous, and during combustion evolve dangerous vapors. Larmes du Diable or ‘Crocodiles’ Tears,’ are formed of metallic sodium, burn with extreme violence if thrown into water, or even if moistened with water, or heated, and scatter particles of caustic alkali, which may inflict serious burns. ‘ Sunshine in Winter Evenings,’ ‘ Fiery Swords,’ &c. are formed of magnesium, and, like the preceding, may cause serious burns. Pyroxylin, which is identical with gun-cotton, is the active agent in the various toys known as ‘Will-o’-the-wisp Paper,’ ‘Parlor Lightning,’ ‘Fireflies,’ &c. The use of these toys in teaching rudimentary chemistry to children and young persons is quite incommensurate with their danger.