PEARL FISHERY.

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better be imagined than described—a stench that defies
exelusion or deodorization, and which is rendered all but
insupportable by the accompanying plague of flies. Medical
organization is, however, very thorough : all arrivals from
[ndia are subject to rigid scrutiny, and by this precaution, in
conjunction with an efficient sanitary staff, the, danger of
spidemic disease is reduced to a minimum.
Pearls are classified according to size, shape, and lustre.
For sizing a series of bowl-shaped sieves is employed, the
holes graduated after a rather intricate formula. The pearls
are next classed with regard to shape, due regard being
given to the lustre or ‘ skin.” Herein is room for much
diversity of opinion, valuers wrangling for hours before an
assessment agreeable to all is arrived at. The final stage is
then reached ; each class of pearls is weighed in turn,
she actual value being thereafter determined by reference
to the market quotations of the day.
Theirregularity and intermittence characteristic of Ceylon
pearl fisheries, already referred to, have been the source of
perennial disquiet to the Government. During the past
century several inquiries were instituted ; endless reasons
for the recurring failures were adduced, but few remedies
were suggested and none were adopted. So matters
remained until the late Governor, Sir J. West Ridgeway,
determined in 1901, after an intermittence of ten years in
the pearling industry, to invoke the aid of biological science
towards the elucidation of the problem. Professor W. A.
Herdman, F.R.S., was approached, and eventually went te
Ceylon in the beginning of 1902, accompanied by the
writer, to investigate. As a result he recently furnished
a voluminous report embracing conclusions based upon two
years’ work.
The chief of the harmful agencies was found to be the
tendency of spat to fall upon unfavourable ground, where if
exposed to the full violence of monsoon storms it is liable
fo be smothered by overwashes of sand; or where, if the
ground is continuously rocky, the oysters eventually become
stunted by the shortage of food induced by overcrowding.
In the latter case the oysters are extremely likely to perish
untimely by the inroads of disease, their tissues, weakened by
semi-starvation, being unable to cope with disease organisms.
Among the chief remedies proposed are the transplantation
 of spat from unfavou rable to favourable ground and the
shinning out of overcrowded beds.
Another result of the investigation has been to determine
the origin and causation of pearls in the Ceylon pearl oyster
(Margaritifera vulgaris). The old idea of pearls being due