A little girl of my acquaintance, on returning from the country after several weeks of absence from her father, said to him,--"Why, papa, I could have you with me whenever I liked, this summer, though it was only your head and shoulders that I could see; but I could place you where I liked and could look at you a long time before you went away." Without knowing it the child exactly described a true vision--her thought of her father was visualized, _externalized_, given a form which had definiteness, which could be placed and examined in detail, and was more or less permanent. Various artificial expedients have been resorted to in order to assist in this process of distinct visualization; and of these artificial means one of the most important and effective is known as crystal-gazing. It is a fact not often commented upon--indeed not often alluded to in general literature--that the crystal has from the earliest times been made use of for the purpose of producing visions, and for divination and prophecy. Not only has the crystal been used for this purpose, but also the mirror, a cup or glass of water or wine, or even some dark and glistening substance like treacle or ink poured into the palm of the hand, have all been used in a similar manner. The same practice is still observed amongst the people of India as well as the Arabs in northern Africa and other localities. An instance or two at the outset will illustrate the method and uses of the procedure. Mr. E. W. Lane, in his "Manners and Customs of the Modern Egyptians," published in 1836, gives this example:-- Mr. Salt, the English consul-general to that country, had greatly interested Mr. Lane by some experiences which he related, and had thus excited his curiosity to witness some of these experiments himself. Mr. Salt had suspected some of his servants of theft, but could not decide which one was guilty; so it was arranged to test the powers of some of the native seers. Accordingly a magician was sent for; a boy was also necessary to act as seer, or as we would say crystal-gazer, and for this purpose Mr. Salt selected one himself. The magician wrote several charms, consisting of Arabic words, on pieces of paper, which were burnt in a brazier with a charcoal fire along with incense and perfumes. He then drew a diagram in the palm of the boy's right hand, and into the middle of this diagram he poured some ink. He then asked the boy to look intently at the ink in the palm of his hand. The boy soon began to see figures of persons in the ink, and presently described the thief so minutely that he was at once recognized by Mr. Salt, and on being arrested and accused of the crime he immediately confessed his guilt.