streams,
are often chosen as easier of access than the plains. If the river-bed
is selected, the first act of the explorers is to seek for the proper
locality where the gem-bearing strata may be found. To ascertain
this, the Cingalese thrust a long iron rod of ten or twelve feet in
length into the earth, and test the nature of the sub-soil. By means of
long practice the natives can adroitly penetrate the earth to a
considerable depth; and, by the resistance to the movement of the rod,
can detect the gem deposit of which they are in search.
"If
the indications are good, the natives proceed to build a hut if they
are at a distance from their village, and prepare for the operations,
which often extend over many weeks. After diverting a part of the force
of the stream so as to form a quiet pool, they proceed to excavate the
sand and gravel within a certain area. In order to accomplish this they
use hoes with handles fifteen or more feet in length. The top strata
are hurriedly raked up and thrown away; but as the pit deepens and the
gem stratum is approached, the work is performed with greater care. As
soon as the hoes bring up fragments and boulders of white quartz, or
strike thin ferruginous crust, every particle of the gravel drawn up is
carefully preserved. The gravel and sand thus obtained are then placed
in large baskets woven of split bamboo and shaped to a conical point at
the bottom. The basket thus filled is placed in the current of water,
and its contents washed by imparting to it a circular motion. This
washing process is kept up until the stones, gravel, and lesser
particles are cleansed. During this operation the gems, which are much
heavier than common stones, settle at the bottom of the basket, and
are there collected together, so that when the superincumbent gravel is
removed, the sapphires, garnets, zircons, etc., are easily discovered
at the bottom and removed. This is the manner in which the wet diggings
are carried on, and is the easiest mode of exploration; but it is by no
means as sure, or often as profitable, as the operations in dry ground
on the river banks or in the plains. The dry diggings are much more
laborious, as the soil is firmer, and the gem strata must be
transported to water to be washed and sifted. These dry deposits are
found the richest beneath the alluvial plains, which seem to have been
in distant times shallow lakes and lagoons.
" The gem stratum, called mellan, is
always well defined, and occurs at a certain depth, which seems to
correspond to the bottom of the lake at a definite period. This depth
varies from two to twenty feet, and is perhaps even greater; but the
natives rarely excavate below the depth of twenty feet. This peculiar
formation, which is generally
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