XXIV Introduction. 
pearls. It is a remarkable fact that, according to Mrs. 
Zelia Nuttall, the people who make use of purple in 
Mexico are also famed for their gold-work, an association 
which has probably survived for twenty centuries. In 
Ireland also the king who is reputed to have first smelted 
gold in that island is also said to have introduced the art 
of making purple. Both in the Old and New Worlds 
purple was not only made and used in the same way for 
staining threads for weaving, but it was also employed 
for colouring precious manuscripts and as a cosmetic. If 
it be argued that purple was invented independently in 
the New World it must be remembered that the method 
of its production is a complex and difficult process, which 
in itself is sufficient to raise a doubt as to the likelihood 
of such a discovery being made more than once. 
There are reasons for believing that all these special 
uses of shells were spread abroad along with the complex 
mixture of arts, customs and beliefs associated with the 
building of megalithic monuments. 
The earliest use of the conch-shell trumpet was in the 
Minoan worship in Crete. Thence it spread far and wide, 
until it came to play a part in religious services, Christian 
and Jewish, Brahman and Buddhist, Shinto and Shaman- 
istic, in widely different parts of the world—in the Medi- 
terranean, in India, in Central Asia, in Indonesia and 
Japan, in Oceania and America. In many of these places 
it was supposed to have the definite ritual object of 
summoning the deity. In the New Testament the sound 
of the trumpet is the signal for the resurrection. Like 
the cowry it was used in marriage and funeral ceremonies, 
in connexion with harvest rites and circumcision, in the 
ritual of initiation into secret societies, in the ceremonials 
before sacred images, in the rites of drinking (such as 
soma-worship and kava) and of head-hunting. 
