thirty-five miles from Leghorn, which bore many evidences of having been worked in ancient times. It closely resembles the Parian in color and grain, works smoothly, and takes a high polish.

White marbles were also obtained by the ancients from Mount Phelleus, Rhamnus, and Sunium, in Attica; Demetrias, in Thessaly; on the river Sangarius, in Phrygia; from near Alexandria Troas; from Mount Prion, near Ephesus; from Cappadocia, and from Mount Libanus, the modern Lebanon.

The marbles of Phelleus, Rhamnus, and Sunium, were of good color, but were coarse, and less homogeneous than the Pentelic. The Sangarian marble was sometimes called Coralitic. The Cappadocian was called Phengites (Péyyos), on account of its translucence. The temple of Fortuna Seia, built by Nero within the precincts of his Golden House, was built of this stone; and, although it had no windows, it is said to have been perfectly light when the door was closed. The marble of Mount Libanus, usually called Tyrian, was probably the material of Solomon's Temple and of Herod's palace. The Scala Santa in the Lateran Palace, Rome, said to have been brought from Pilate's house in Jerusalem, is of this marble, which is a clear blue-white.

The Proconnesian marble, a pure white with black veins, was quarried in the island of Proconnesus, in the Propontis. The celebrity of this stone has changed the name of the island to Marmora, and also given its modern name (Sea of Marmora) to the Propontis. This marble was also called Cyzican, because it was largely used in the city of Cyzicus, opposite the island in Mysia. The palace of Mausolus, at Halicarnassus, was built of it. It was also much used at Constantinople, under Honorius and the younger Theodosius. Several columns of it in the mosque of St. Sophia were spoils of the temple of Cybele at Cyzicus.

A white marble, with yellow spots, was brought from Cappadocia, and a similar marble from Rhodes, but the spots were of a brighter, more golden, yellow. White marble, with black spots, was quarried in the Troad.

But the most beautiful of the antique variegated marbles, with a white base, was the Synnadic, Docimæan, or Docimite, sometimes called marmor Phrygium. It was quarried at the village of Docimia, not far from Synnada, in Phrygia Major. The ancient authorities generally describe it as pure white, marked with red or purple veins, which the poets compared to the blood of Atys, slain at Synnada; but Hamilton, who visited the quarries about 1835, says that they yield several different kinds. He mentions white, bluish-white, white with yellow veins, white with blue veins, and white with blue spots, the latter having almost a brecciated appearance. He describes the principal quarry as worked horizontally into the hill, the sides of which are cut away perpendicularly to a great height to secure the splendid columns for which it was famous. Strabo says that pillars

and slabs of surprising magnitude and beauty, approaching the alabastrite marble in variety of colors, were conveyed thence to Rome, notwithstanding the long land-carriage of more than 100 miles to the place of shipment. The quarries are entirely surrounded by trachytic hills, to which, says Hamilton, the marble "owes its crystalline and altered character, being to all appearance a portion of the older secondary limestone caught up and developed by the protruded volcanic rocks, and crystallized by igneous action."

The alabastrites marble of the ancients, or onychites, was not a marble proper, but a hard carbonate of lime, identical in composition with stalagmite, the modern alabaster. It was quarried, says Pliny, near Thebes, in Egypt, and Damascus. When first brought to Rome it was considered almost a precious stone, and was made into cups and small ornaments, such as the feet of couches and chairs. When Balbus decorated his theatre, in the time of Augustus, with four small columns of this stone, it was noted as an unprecedented occurrence; but, in the reign of Claudius, Callistus, a freedman of that emperor, adorned his banquet hall with thirty large columns of alabastrites. The ancient quarries were reopened by Mehemet Ali, Viceroy of Egypt, to obtain material to build his mausoleum at Cairo. The four magnificent pillars of this marble that support the baldacchino over the altar in the church of San Paolo fuori le Mura, in Rome, were presented by him. Each is a monolith forty feet long.

Of the yellow marbles of antiquity, that called by the Italians giallo antico is the rarest and most beautiful. There are several varieties of it, varying in tint from a cream-yellow to the deepest chrome-yellow, sometimes shading into red and purple hues. Some is as bright as gold (giallo dorato), some of an orange-shade (giallo capo), and some, extremely rare, of a canary-color (giallo paglia). The ancient writers compared it to saffron, to sunlight, and to ivory grown yellow with age. Some of it is variegated with black or darkyellow rings. The grain is exceedingly fine. Its colors are derived entirely from carbonaceous matter. Among the finest existing specimens of this marble are the large columns in the Pantheon at Rome, and a single pair in the Arch of Constantine. The giallo antico was called marmor Numidicum by the Romans, but the precise site of the quarries is not yet ascertained. M. Fournel believes that the yellow marble of Philippeville, Algeria, which closely resembles it in varying tints, is identical with it. The island of Melos and Corinth also produced yellow marbles, and in the time of Justinian a marble of a fiery yellow was quarried in the neighborhood of Jerusalem.

Among the most celebrated marbles of the ancient world was the rosso antico, or red antique. Its color passes from a red, almost scarlet, to a wine-lees or blood-red, which is divided by parallel layers of white, and sometimes also intersected by a network of delicate black veins. Its variation in tint is probably according to the quan

tity of the oxide of iron contained in it. Until lately this marble was known only through its remains, and it has generally been ascribed to Egypt. The largest ancient specimens preserved are the fourteen slabs composing the double flight of steps in the church of San Prassede, Rome. Napoleon I. at one time intended to carry these to Paris to ornament his throne. There are several statues of rosso antico, including the "Antinous" in Paris and the "Marcus Agrippa" in the Grimani Palace, Venice, and many medallion portraits. It is now ascertained that this beautiful marble was not Egyptian, but Greek. It was quarried on the coast of the gulf of Laconia, near what is now the bay of Scutari. The quarry lies near the sea, and large blocks cut by the ancients are still to be seen there. In 1851 the Greek Government sent specimens from it to the London Exposition, and it was fully recognized as the famous rosso antico.

There are many varieties of the marble called red and white antique, but they are so near alike that it is impossible to distinguish them by description alone. They are variously called by the Italians rosso annulato, serpentelo, vendurino, fiorito, cotonello, etc. They are found only in the Roman ruins, and their quarries are unknown. The marble called cervelas is of a deep red, with numerous gray and white veins. It is supposed to have been brought from Africa.

The ancients were acquainted with many kinds of green marble, one of the most noted of which was the marmor Atracium, called by Julius Pollux Thessalian, and identical with the verde antico of the Italians. The quarries were on Mount Ossa, near the entrance of the vale of Tempe, and not far from Atrax in Thessaly, whence it derived its name. It is a species of breccia, whose paste is a mixture of tale and limestone, interspersed with fragments of white marble. But the verde antique marbles differ from the modern breccias in that the colors are so blended that the line of demarkation is not perceptible. The Erechtheum in Athens was adorned with columns of verde antique, and it was one of the marbles selected by Justinian for the decoration of St. Sophia. The eight splendid columns of it still to be seen in the mosque are said to have been taken from the temple of Diana at Ephesus.

The celebrated Carystian marble, the cipolino verde of the Italians, derived its name from Carystus, a town at the foot of Mount Oche, in the island of Euboea, where it was quarried. The temple of Apollo Marmarinus of Carystus was named from this quarry. It is a true steatitic limestone or cipolin, and is of a beautiful grayish green, with white zones and spots, and sometimes sprinkled with different colors. It was easily obtained in very large blocks, suitable for columns, and was largely used in the temples and other public buildings in Athens and Rome. An English traveler, who visited the quarry lately, found seven entire columns on the site, about three miles from the sea, just as they were left by the ancient workmen.

The marmor Lacedæmonium, Laconicum, or Spartum, of the Romans has always been regarded as a species of verde-antique marble. Clarke says that it differed from the Atracian only in being variegated with black or dark-green serpentine instead of with white. But M. Boblaye, the mineralogist of the French commission to the Morea, has proved pretty conclusively that it was not a marble but a true porphyry, and probably identical with the ophites of the ancients, which Pliny says was so called from its resemblance to the skin of a serpent (opic). Pausanias calls it Crocean stone (Kpókɛwv 2i0os). The French discovered the quarries near the ancient Croceæ, on the road from Sparta to Gythium, and about two miles from the modern village of Levétzova, in Laconia. The stone is of a dark grassgreen, strewed with little parallelograms of a lighter green, sometimes approaching white and sometimes yellow. Procopius compares its color to emerald, and Statius and Sidonius call it a grass-green. Eurycles, the Spartan architect, used this stone in decorating the baths of Neptune at Corinth; and it was quarried to a large extent by the Romans, who enriched the monuments of Greece, Italy, and Gaul, with it.

The Augustan and Tiberian marbles, so fashionable in Rome under those emperors, were obtained in Egypt. They are breccias composed of fragments of greenstone, gneiss, and porphyry, cemented with a calcareous paste. They are similar in color, a bright green, spotted and streaked with dark green, reddish gray, and white; the only difference being, according to Pliny, that in the Augustan the figures undulate and curl to a point, while in the Tiberian the streaks are not involved, but lie wide asunder. It is probable that these marbles were quarried in the mountains between Thebes and the Red Sea. Inscriptions in the ancient quarries there, near the well of Hammamat, show that they were worked in the sixth dynasty of Manetho. A green marble called Memphites was quarried near Memphis in Egypt.

There were many other varieties of green marble known to the ancients, such as the red-spotted green antique, having a dark-green ground marked with small red and black spots and white fragments of entrochi; the marmo verde paglioco, yellowish green; and leek marble, of the color of a leek; but they exist only in small fragments, and their quarries are unknown. Another variety of green marble was found in the island of Tenos.

A blue marble is said to have been obtained in Libya. The island of Naxos yields a dark blue elegantly striped with white, Tenos a light blue veined with dark blue, and Seyros many kinds of blue and violet breccias, with other colors variously disposed. Seyros was one of the chief places whence the ancients derived their variegated marbles, and its quarries furnished many varieties closely resembling the famous marbles of other localities. Strabo says it pro

duced the Carystian, Deucalian, Synnadic, and Hierapolitic marbles. The quarries of Tenos are still worked to some extent, but those of Scyros and Naxos remain almost as the ancients left them.

Of the black marbles of antiquity that now called nero antico, or black antique, was the most celebrated. It is more intensely black than any marble now quarried, the black marbles of France appearing almost gray beside it. It occurs only in sculptured pieces, and its origin is unknown; but Faujas discovered a quarry which had been worked by the ancients, about two leagues from Spa, not far from Aix-la-Chapelle, the marble of which closely resembles the ancient specimens. The largest masses known of nero antico are two columns in the church of Regina Coeli at Rome, but there are also some fine specimens in the Museum of the Capitol and in other collections. Some suppose it to be identical with the marmor Lucul lum, which was introduced at Rome by Lucullus in the first century B. C., according to Pliny from Melos (another reading is Chios), but according to other authorities from Egypt or Libya, whence it is sometimes called marmor Libycum. Pliny says that Marcus Scaurus had pillars of it thirty-eight feet high in the atrium of his house. The Chian marble, a deep, transparent black, sometimes variegated with other colors, was quarried on Mount Pelinæus, in the island of Chios. A fine black marble was quarried on Mount Tænarus, in Laconia, and in the island of Lesbos, and a blue-black marble in Lydia. One of the most beautiful of the antique breccias, the African breccia, has a deep-black ground, variegated with fragments of grayish white and deep red or purplish wine-color. The grand antique breccia consists of large fragments of black marble united by veins of shining white. Columns of this and of African breccia are in the Paris Museum, but their quarries are unknown.

ON THE WONDERFUL DIVISIBILITY OF GOLD AND OTHER METALS.

IT

BY ALEXANDER E. OUTERBRIDGE, JR.,

ASSAY LABORATORY, UNITED STATES MINt, philadelpHIA.

T is both curious and interesting to notice how frequently original investigators, working from different standpoints, and with entirely dissimilar objects in view, will, independently of each other, accumulate a mass of observations corroborative of some one physical law, but which require to be collated in order to reveal their mutual relations.

The motive of this paper is to collect together several observations illustrating the divisibility of gold (made either as the direct