SCIENCE AND INDUSTRY. 
tropical Australia may in the future support a large resident population 
of fisher folk. At present its resources are exploited by an alien, 
coloured, and nomadic host. md 
Pearling, or shelling as it is locally called, is the most important 
of the marine tropical industries. The pearling grounds extend for 
more than 2,000 miles along the northern coast of Australia. Here, 
in 1913, were employed 4,000 men, the product of whose labour was 
valued at £444,000. As a business, pearling began in Western Aus- 
tralia in 1861, but the beds of Queensland were not worked till a few 
years afterwards. Not until 1881 had the fishery grown sufficiently 
important to attract the attention of the Government. In that year 
various regulations, such as licences for boats and divers, were instituted. 
About ten years afterwards the law forbade the taking of immature 
oysters, placing on “chicken shell” a limit of a diameter of 6 inches. 
From time to time all the beds have been exhausted by over-fishing, 
but they have recuperated after a few years’ rest. 
COLLECTING ON REEF. 
Three kinds of pearl shell are fished in Australian waters—the 
Golden-lip or Silver-lip, the Black-lip, and the Shark-Bay shell. Of 
these the Golden-lip (Pinctada maxima) is the largest, the most lus- 
trous, and therefore the most valuable in the world. It occurs north of 
Townsville, on the Queensland coast, round to Exmouth Gulf on the 
west. In the early days of the industry, when oysters might grow to 
their full natural size, the shell often attained a weight of 6 or 7 lbs. 
a pair; now 2 lbs. are considered a fair marketable shell. Having 
such brilliant nacre, this species forms beautiful pearls. But as a 
pearl is the consequence of disease, it more frequently occurs in stunted 
and misshapen shells. The staple of the industry is the mother-of-pearl, 
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