uses of the wheel in Indian symbolism, are irrelevant, for the object
to be explained is not really a wheel but a barrel, large or small,
containing written prayers, or even a whole library. Those who turn
the barrel acquire all the merit arising from repeating the
prayers or reading the books. In Tibet this form of devotion is a
national mania. People carry small prayer wheels in their hands as
they walk and place large ones in rivers to be turned by the current.
In China, Japan and Korea we find revolving libraries and occasional
praying machines, though not of quite the same form as in Tibet,[1050]
but, so far as I know, there is nothing to show that these were not
introduced from Tibet into China and thence found their way further
East. The hypothesis that they were known in India and thence exported
to Tibet on one side and China on the other naturally suggests itself,
but the total absence of praying machines in India as well as in the
ruined cities of Central Asia and the general Hindu habit of regarding
scriptures and spells as words rather than written documents lend it
no support. It may be that when the illiterate Tibetans first became
acquainted with written prayers, they invented this singular method of
utilizing them without reading them.

Equally obscure is the origin of the formula Om mani padme[1051]
hum, which permeates Tibet, uttered by every human voice, revolved in
countless machines, graven on the rocks, printed on flags. It is
obviously a Dharani[1052] and there is no reason to doubt that it
came to Tibet with the first introduction of Buddhism, but also no
record. The earliest passage hitherto quoted for its occurrence is a
Chinese translation made between 980 and 1001 A.D.[1053] and said to
correspond with the Kanjur and the earliest historical mention of its
use is found in Willelm de Rubruk (1254) and in the writings of
Bu-ston.[1054] The first legend of its origin is contained in the
Manikambum, a work of doubtful age and authorship but perhaps as
old as the fifteenth century.[1055] The popularity of the prayer may
date from the time when the pontiffs of Lhasa were recognized as
incarnations of Avalokita. The first and last words are mystic
syllables such as often occur in these formulae. Mani padme is
generally interpreted to mean the jewel in the lotus,[1056] but Thomas
has pointed out that it is more consonant with grammar and usage to
regard the syllables as one word and the vocative of a