The pearls adherent to the valve are more or less irregular in their shape; they are sold by weight. Those found in the body of the animal, and isolated, are called _virgin pearls_. They are globular, ovoid, or pyriform, and are sold by the individual pearl. In cleaning them, they are gathered together in a heap in a bag, and worked with powdered nacre, in order to render them perfectly pure in colour and round in shape, and give them a polish; finally, they are passed through a series of copper sieves, in order to size them. These sieves, to the number of a thousand, are made so as to be inserted one within the other, each being pierced with holes, which determine the size of the pearl and the commercial number which is to distinguish it. Thus, the sieve No. 20 is pierced with twenty holes, No. 50 with fifty holes, and so on up to No. 1,000, which is pierced with that number of holes. The pearls which are retained in Nos. 20 to 80, said to be _mill_, are pearls of the first order; those which pass and are retained between Nos. 100 and 800 are vivadoe, or pearls of the second order; and those which pass through all the others, and are retained in No. 1,000, belong to the class _tool_, or seed pearls, and are of the third order. They are afterwards threaded; the small and medium‐sized pearls on white or blue silk, arranged in rows, and tied with ribbon into a top‐knot of blue or red silk, in which condition they are exposed for sale in rows, assorted according to their colours and quality. The small or seed pearls are sold by measure or weight. We cannot wonder at the estimation in which these beautiful productions of nature have always been held. Our Lord speaks of “a merchantman seeking goodly pearls,” and once of a “pearl of great price.” The ancients held them in great esteem. Ahasuerus had a chamber with tapestry covered with valuable pearls. Julius Cæsar offered to Servilia, the mother of Brutus, an “Orient pearl,” valued at money representing a million sesterces;(27) Cleopatra’s expensive draught is estimated by Pliny at the equivalent of £80,729; Lollia Paulina, wife of Caligula, used to put on about £200,000 sterling’s worth of them on high days and holidays. In our own country Sir Thomas Gresham powdered up a pearl worth £65,000, in Queen Elizabeth’s time, and drank it up _à la_ Cleopatra, excepting only that he took it in wine instead of in vinegar. It was done in vain‐ glory to outshine the Spanish ambassador, with whom he had wagered to give a more expensive entertainment than he could. Scottish pearls, which are slightly bluish in tint, were much celebrated in the Middle Ages, and were sent to London from the rivers Tay and Isla; the trade carried on in the present century, the Rev. Mr. Bertram tells us, has become of considerable importance.