A great deal of art is shown in the stringing and mounting of beads. The simplest form is a single strand, a twisted string of vegetable fiber, a strip of buckskin, or a bit of sinew being passed through the perforations. Again, rows of strands are placed side by side and fastened at intervals in such a manner as to keep them approximately parallel, or the beads when long are put on equidistant cross strands, the longitudinal strands serving to keep them in place; they are also woven into the fabric by being mounted upon one of the strands before twisting. It is also a very usual practice to sew them on strips of cloth or buckskin, patterns being produced by using beads of different colors. The manner of stringing in the manufacture of belts will be given in detail under Mnemonic Uses of Beads. BEADS AS CURRENCY. It will probably be impossible to prove that the prehistoric peoples of North America employed a medium of exchange in a manner corresponding to our use of money. It is a well-known fact, however, that a currency of shell beads was in general use throughout the Atlantic coast region very early in the historic period. Of all objects within the reach of savage peoples, shells, either in their natural forms or in fragments artificially fashioned for convenience of use, are the best adapted for such a purpose. In examining the contents of ancient cemeteries and mounds where all objects of value were to some extent deposited, we find no other relics that could have been conveniently used for such a purpose. It is not probable that objects subject to rapid decay, such as wood, fruits, and seeds, could ever have come into general use for money, although such objects are employed to some extent by savages in different parts of the world. The unlimited supply or easy manufacture of these objects would be against their use for this purpose, whereas the difficulty of shaping and perforating the flinty substance of shells would prevent such a plentiful production as to destroy the standard of value.