Shell of Dipsas plicatus, with attached metal figures of Buddha coated with nacre

Shell of Dipsas plicatus, with attached porcelain beads coated with nacre

The Linnean Society of London apparently possesses some of the very pearls grown by Linnæus, as well as several manuscripts which throw much light on this subject. It appears from the latter that, under date of 6th February, 1761, Linnæus wrote that he “possessed the art” of impregnating mussels for pearl production, and offered for a suitable reward from the state to publish the “secret” for the public use and benefit. A select committee of the state council of Sweden was appointed to confer with him, and on 27th July, 1761, the naturalist appeared and verbally explained his discovery. After various meetings, the select committee approved the “art” and recommended a compensation of 12,000 dalars (about $4800). It does not appear that the award was paid, and the following year the secret was purchased by Peter Bagge, a Gothenberg merchant, for the sum of 6000 dalars. On 7th September, 1762, King Adolph Frederick issued a grant to this merchant “to practice the art without interference or competition.”[[327]]

Peter Bagge was unable to exercise the rights which he had acquired, nor was he able to dispose of them to advantage. On his death the memorandum of the secret became lost, and it was not found until about 1821, when it was discovered by a grandson, J. P. Bagge. Under the date of 27th February, 1822, the King of Sweden confirmed to this grandson the privileges which his ancestor had purchased in 1762. Fruitless efforts were again made to dispose profitably of the rights either to individuals or to the Swedish government.

The details of Linnæus’s “secret” have never been published authoritatively. In his “History of Inventions,” Beckmann states that before the naturalist thought of the profits that might accrue from his discovery, he intimated the process in the sixth edition of his “Systema naturæ,” wherein he states: “Margarita testæ excrescentia latere interiore, dum exterius latus perforatur.”[[328]] “I once told him,” says Beckmann, “that I had discovered his secret in his own writings; he seemed to be displeased, made no inquiry as to the passage, and changed the discourse.”[[329]]

In the second volume of his edition of “Linnæus’s Correspondence,”[[330]] Sir J. E. Smith remarks: “Specimens of pearls so produced by art in the Mya margaritifera are in the Linnean cabinet. The shell appears to have been pierced by flexible wires, the ends of which perhaps remain therein.” Referring to this remark, J. P. Bagge comments: “This is the nearest I have seen any one come to truth, but still it will be remarked by reading the ‘secret’ that more information is required to enable persons to practice the art.”

After a thorough examination of the manuscripts and other material, Professor Herdman concludes that the essential points of Linnæus’s process are to make a very small hole in the shell and insert a round pellet of limestone fixed at the end of a fine silver wire, the hole being near the end of the shell so as to interfere only slightly with the mollusk, and the nucleus being kept free from the interior of the shell so that the resulting pearl may not become adherent to it by a deposit of nacre.[[331]]

Shortly after Linnæus communicated with the Swedish government and before his death, it was learned in Europe that the art of producing “culture pearls” by a somewhat similar process had been practised by the Chinese for centuries.[[332]] They used several forms of matrices or nuclei, but principally spheres of nacre and bits of flat metal or molded lead, which were not infrequently in conventional outline of Buddha. In the spring or early summer, these were introduced under the mantle of the living mollusk after the shell had been carefully opened a fraction of an inch, and the animal was then returned to the pond, or lake. The mollusk did its work in a leisurely way, like some people who have little to do, and many months elapsed before it was ready for opening and the removal of the pearly objects.

The most satisfactory description we have seen of this process appears to be that communicated nearly a century later to the London Society of Arts by Dr. D. T. Macgowan,[[333]] through H. B. M. plenipotentiary in China, from which this account is abridged and modified.