Why Do Cats Turn Wheels?
Tibetan prayer wheels (called Mani wheels by the Tibetans) are devices for spreading spiritual blessings and well being. Rolls of thin paper, imprinted with many, many copies of the mantra (prayer) Om Mani Padme Hum, printed in an ancient Indian script or in Tibetan script, are wound around an axle in a protective container, and spun around and around. Typically, larger decorative versions of the syllables of the mantra are also carved on the outside cover of the wheel.
Tibetan Buddhists believe that saying this mantra, out loud or silently to oneself, invokes the powerful benevolent attention and blessings of Chenrezig, the embodiment of compassion.
Viewing a written copy of the mantra is said to have the same effect -- and the mantra is carved into stones left in piles near paths where travelers will see them. Spinning the written form of the mantra around in a Mani wheel is also supposed to have the same effect; the more copies of the mantra, the more the benefit.
Traditionally wheels were not used at all in Tibet except for spiritual purposes -- carts and similar wheeled devices were known from other cultures, but their use was intentionally avoided. The earliest known mention of prayer wheels is in an account written by a Chinese pilgrim, in 400 AD, while traveling through the area now known as Ladakh. The idea is said to have originated as a play on the phrase "turn the wheel of the dharma," a classical metaphor for Buddha's teaching activity.
Mani wheels are found all over Tibet and in areas influenced by Tibetan culture. There are many types of Mani wheels, but small hand-held wheels, like the one shown here, are the most common by far. Tibetan people carry them around for hours, and even on long pilgrimages, spinning them any time they have a hand free.
Larger wheels, which may be several yards (meters) high and one or two yards (meters) in diameter, can contain myriad copies of the mantra, and may also contain sacred texts, up to hundreds of volumes.
They can be found mounted in rows next to pathways, to be spun by people entering a shrine, or along the route which people use as they walk slowly around and around a sacred site -- a form of spiritual practice called circumambulation.
stream spins prayer wheel
Wheels are also placed where they can be spun by wind or by flowing water. Smaller mounted wheels can be spun by the heat rising from a flame or by steam from a stove, or placed on a tabletop to be spun by hand.
Tibetan Buddhist Mani wheels are always spun clockwise, as viewed from above, for any or all of several reasons: It rotates the syllables of the mantra so that they would pass a viewer in the order that they would be read, it follows the direction of the sun, and it matches the clockwise circumambulation of stupas. Practitioners of Bon, the pre Buddhist spiritual tradition of Tibet, spin their prayer wheels counter-clockwise, the same direction they use in circumambulation.
*thank you http://www.dharma-haven.org/tibetan/prayer-wheel.htm for this excerpt about prayer wheels.