One of the oldest form of mediumship appears to be Scrying. An ancient act of divination for the purpose of clairvoyance, and was in the past, and still is to some degree, a great favourite of the Gypsy fortune teller because one of the practices of scrying is the use of a crystal ball.
But scrying dates right back to ancient Egypt to around 3000 years BC. In early Britain the Celtic population practised many forms of scrying. The items used in those gone by days were things such as black glass, polished quartz, water, crystal and any other transparent or light catching item that might have been available to them.
To-day of course, scrying can be carried out by employing any number of different surfaces which include, water in a dark bowl, mirrors, crystals and crystal balls, tea leaves and the embers of a night fire, and believe it or not, looking into the eyes of a person sat near or opposite to you in a candle lit room.
It seems however, that favorite of the gypsy fortune teller is the Crystal Ball, but the favorite of other gifted people seems to be the mirror and one that is preferably black, although a silver mirror does work. Some say that water should be run across the face of the mirror as you stare into it.
Water scrying is another form. Water represents the collective unconsciousness - the continuum - the flow of all things in the universe back to one source. When scrying in a bowl of water for instance, the bowel needs to be black or painted black, the other alternative being adding black ink into the water to make the water black.
Crystal scrying is probably the most common, and involves the use of either a crystal ball or a crystal skull. The crystal can be clear quartz, lead crystal or crystal with fusions, it makes no difference, but you do have to feel comfortable with it. The larger the crystal is, the better.
What ever system you employ, it needs to be practised or completed in a place that is quiet, where you can shut life out and let your thoughts be heard without distractions, which will enable you to concentrate on the objects that you see. Ideally, pick a place like a bedroom and using only (with care) candle light. Background music can be played, but only that of a meditative type and you should proceed with the usual forms of caution and protection.
Images may first appear as mist, then forming into something more conclusive and recognisable. It is said that if you are scrying with a mirror, you should stare at your reflection at the point of the third eye (centre of the forehead between your eyebrows and above them) keeping your mind blank, you may see your face change, these could be passed lives or you may even see pictures of the past, present or even some futuristic events. It should be pointed out that, you need to keep the mind as blank as possible and do not try to predict what you will see. Let you natural mediumistic powers work and do not force the issue.
Like all things to do with occult matters, nothing happens over night. You may be lucky and get results on your first sitting, but many have to try different items to use until they find one that suits them best.
A most famous person known to have used scrying as a form of divination was, Nostradamus, who employed a small bowl of water as his medium. Another historical figure was alchemist John Dee's assistant Edward Kelly. His crystal ball and wax tablets are on display at the British Museum