To accomplish this metamorphosis, it is necessary to have earthen vases which have little edges or rims near their mouths, and should be of a size sufficiently large to hold suspended the bird or flower which you intend placing in them. You should likewise be provided with stoppers of cork, of a diameter equal to that of their mouths. To make an experiment upon some bird, it is necessary to commence by making a hole in the stopper, sufficiently large to contain the neck of the bird without strangling it. This done, you divide the diameter of the stopper into two equal parts so as to facilitate the placing of it around the neck without doing injury to the bird. The two parts being brought together, you place at the bottom of the vase an ounce of quicklime, and beneath that a quarter of an ounce of sal ammoniac. When you perceive the effervescence commence to take place, you promptly insert the stopper, to which the bird is attached, leaving the neck outside. The plumage of the body, exposed to this effervescent vapor, will become impregnated with the various colors produced by this chemical combination.