Page:Popular Science Monthly Volume 82.djvu/552

548 pearls in one hundred and thirty-three days. These pearls, however, are thin layers of nacre, foimed over a horny basis, which is the first material to be secreted. In the natural process of continued deposition they increase in thickness and solidity and consequently in value. One produced in a green abalone in seven months shows good form and luster. My average time for drilling a hole in the abalone shell, inserting the form and wiring it in place with the numbered metal tag, is eight minutes. This working time might be decreased by an expert laborer doing nothing else, so that the business of raising pearls would be of interest and profit. Mr. C. B. Linton has succeeded in producing similar culture pearls by drilling a hole through the shell center, pushing in a round ball, made from shell, and filling the outside end of the hole with beeswax and cement.

Based upon the fact that each ton of abalone shells represents a certain value of manufactured jewelry and novelties, it is possible to estimate the value of the abalone industry. Shells of the black abalone are sorted into two classes. Each ton of those with fine, pearly centers will make novelties and jewelry worth, at retail, four thousand dollars. The class known as button shells, with plain mother-of-pearl surface, represents a final value of one thousand dollars and the shells of the green abalone, three thousand dollar?. For the fiscal year ending in July, 1912, the following shipments were made from Long Beach and represent the given valuations in manufactured products: thirteen tons of pearl center black abalone shells, fifty-three thousand dollars; forty tons of button black abalone shells, forty thousand dollars; fourteen tons of dried abalone meats at two hundred dollars a ton, twenty-eight hundred dollars; a total of ninety-five thousand eight hundred dollars. The shipping statistics are not complete for the other California ports, but it is demonstrable that the abalone industry may be developed into one of great value.

Much has been said recently in the newspapers concerning the threatened extermination of the abalone. That this is a real danger, and not an idle theory, is apparent to any one familiar with the facts. For instance, near Avalon, Santa Catalina Island, not more than twenty years ago, the green and corrugated abalones were so thick that they rested upon one another four or five deep, all over the rocks. After much searching in this locality during the last year I was unable to find a single specimen. The shells brought up by the divers of the glass-bottomed boats, and eagerly bought by the tourists, have been placed in position previously by the enterprising management. Great shell heaps on San Clemente, San Nicholas and other islands prove the abundance of abalones during the centuries of Indian occupation. Some of the red shells found are unusually large, measuring from twenty to thirty inches in circumference. Necklaces of large abalone