Another form of Psychometric development is that of tracing the past history, surroundings, etc., of metals, minerals, etc. The process is identical to that just described. The mineral is pressed against the forehead, and with closed eyes the person awaits the Psychometric impression. Some who have highly developed the faculty have been able to describe the veins of mineral, metal, etc., and to give much valuable information regarding same, all arising from the psychic clue afforded by a sample of the rock, mineral, metal, etc. There are other cases of record, in which underground streams of water have been discovered by Psychometrists, by means of the clue given by a bit of earth, stone, etc., from the surface. In this, as in the other phase mentioned, ~practice~, ~practice~, ~practice~, is the summing up of the instruction regarding development. ~Crystal Gazing.~ We consider the use of the Crystal Glass Ball, or other forms of what the ancients called "The Magic Mirror," to be the best plan of developing Psychomantic Power. As we have already explained, this method serves to focus the concentrated desire, will, and thought of the person, and thereby becomes the starting point for the Astral Tube, of which we have frequently spoken in this work. The student becoming proficient in this class of phenomena, passes by easy, gradual and natural stages to the higher and more complex phases of the subject. The "Magic Mirror" (of which the Crystal is but a form) was used by the ancient Occultists in developing the powers of their students, and in all countries, and in all ages, it has played a similar part in the process of developing psychic powers, and serving as a focal point for the erection and operation of the Astral Tube, in Psychomancy and other forms of occult and psychic phenomena. At this point, we wish to tell you that there is no special virtue or magical properties or qualities in the Crystal itself--it is merely an instrument for Astral Vision, just as the telescope, microscope and other optical instruments are instruments employed in the phenomena of physical vision. It is true that the atomic and molecular characteristics of glass, crystal, etc., tend to produce the best results, but, after all, water, ink, etc., have been, and may be similarly used. No, there is no special "magic" in the crystal itself, so do not allow yourself to fall into any superstition regarding its use.