are rare, the poisoning developing as a rule much less rapidly. In workers in rubber factories, in which there is much vapor of CS, there develop disturbances of temper, pressure feelings on the head, heat, and the feeling as if the blood would burst through the skull, with headache. There may also be symptoms of irritation of the bronchi, coughing, and roughness of the voice, etc. Treatment is fresh air and symptomatic.

Carbon Monoxide, or Carbonic Oxide, CO, is produced, in addition to the dioxide, when carbon is burned with a limited supply of air or oxygen. It is also generated by passing carbon dioxide through a red-hot bed of carbon, in accordance with the equation CO2+ C=2CO. For experimental purposes the gas may be generated by decomposing oxalic acid by heating it with strong sulphuric acid, and passing the gases that are evolved through a solution of caustic soda to absorb the carbon dioxide that is present. Carbon monoxide is colorless, and has a density about 0.97 times that of air. It burns with a lambent, blue flame that is often seen in coal fires that have been freshly supplied

with fuel.

Carbon Oxychloride. See PHOSGENE. Carbonado, or Carbon, a massive, black or dark-gray variety of diamond, also called "black diamond." Though possessing the adamantine or resinous luster of the crystallized variety, it is opaque and, therefore, of no value as a gem. It is the hardest substance known and this fact makes it the most desirable for use in diamond drills; it therefore sells for as high a price per carat as one carat rough gem diamonds (q.v.). Being without cleavage it is less brittle than the crystals, and owing to its somewhat porous structure, its specific gravity is less, 3.15 to 3.29. The commercial supply comes exclusively from the province of Bahia, Brazil, where it occurs in angular fragments which occasionally show a rough cubic outline.

Carbonari, kär-bō-nä'rē (colliers, or more strictly, charcoal-burners), the name of a large political secret society in Italy. According to Botta's 'Storia d'Italia) the Republicans fled, under the reign of Joachim (Murat), to the recesses of the Abruzzi, inspired with an equal hatred of the French and of Ferdinand. They formed a secret confederacy, and called themselves carbonari. Their chief, Capobianco, possessed great talents as an orator. Their warcry was "Revenge for the lamb mangled by the wolf!" When Murat ascended the throne of Naples he employed Maghella, a Genoese, in the department of police, and afterward as minister. All his efforts were directed to the union and independence of Italy, and for this purpose he made use of the society of the Carbonari. The ritual of the Carbonari was taken from the trade of the charcoal burner. Clearing the wood of wolves (opposition to tyranny) was the symbolic expression of their aim. By this they are said to have meant at first only deliverance from foreign dominion; but in later times democratic and anti-monarchical principles sprang up. They called one another good cousins. No general union of the order under a common head seems to have been effected. The separate societies in the small towns entered into a connection with each other, but this union extended

no farther than the province. The place of assembly was called the hut (barraca); the surrounding neighborhood was called the wood; the meeting itself was distinguished as the sale (vendita). The confederation of all the huts of the province was called the republic, generally bearing the ancient name of the province. The chief huts (alta vendita) at Naples and at Salerno endeavored to effect a general union of the order, at least for the kingdom; but the attempt appears to have been unsuccessful. The order, soon after its foundation, contained from 24.000 to 30,000 members, and increased so rapidly, that it spread through all Italy. In 1820, in the month of March alone, about 650,000 new members are said to have been admitted; whole cities joined the society. The military, in particular, seem to have thronged for admission. The religious character of the order appears from its statutes: "Every Carbonaro has the natural and inalienable right to worship the Almighty according to the dictates of his conscience." After the suppression of the Neapoli

tan and Piedmontese revolution in 1821, the

Carbonari throughout Italy were declared guilty of high treason, and punished by the laws. Meantime societies of a similar kind had been formed in France, with which the Italian Carbonari amalgamated, and Paris became the headquarters of Carbonarism. The organization took on more of a French character, and gradually alienated the sympathies of the Italian members, in order to form the party of Young Italy. a number of whom dissolved connection with it,

Car'bonates. See CARBON DIOXIDE.

Car'bondale, Pa., a city of Lackawanna County, situated on the Lackawanna River, 110 miles north-northwest of Philadelphia; and on the Erie, the Delaware & H., and the New York, O. & W. R.R.'s. It is the centre of an important anthracite coal-field, and the principal industry is mining. There are also machine-shops, foundries, etc. As it is in a monuntain region with fine scenery, it is also a summer resort. Pop. (1910) 17,040.

Carbonear, kär'bon-er, Newfoundland, a port of entry on the eastern side of the peninsula separating Trinity Bay from Conception Bay 25 miles in a northwesterly direction from St. John's. Pop. (1901) 3,703.

Carbonic Acid, or Carbonic Acid Gas. See CARBON DIOXIDE.

Carbonic Anhydrid. See CARBONIC DIOXIDE.
Carbonic Oxide. See CARBON MONOXIDE.

Carboniferous Limestone, or Mountain Limestone, certain limestones of Lower Carboniferous age, as named by Murchison and other English geologists. In the United States the silver-lead ores of Leadville and other Rocky Mountain camps, and the zinc and lead ores of southwestern Missouri, are in limestones of Carboniferous age. See CARBONIFEROUS SYS

TEM.

Carboniferous Period, the last of the great time divisions of the Paleozoic Epoch. During it were laid down vast beds of plantremains now turned to coal, whence the name. It is true that coal fields of later age than Carboniferous are known, particularly in North America, but the important coal fields of Europe and of eastern North America are of Carboniferous age. In North America, when the

was

Carboniferous Period began, most of New England, eastern Canada, and Newfoundland was land, though two long, narrow arms of the Gulf of St. Lawrence extended to Narragansett Bay. West of the Blue Ridge Mountains, or Appalachian uplift, was a great interior sea, in places quite deep and extending to the Rocky Mountains. During Carboniferous time, by a gradual uplift, the northeastern part of this sea divided into two bays, one covering nearly all of Pennsylvania, West Virginia, eastern Ohio, and Kentucky, the other covering southern Michigan. In the west the old land surfaces sank, and great areas along the whole Rocky Mountain region and beyond were covered by the sea. In general, the Carboniferous in North America was a period of slow changes of land surface with no volcanic outbursts. In the eastern part of the continent the land sank, then gently rose, over great areas, forming vast swamps, with numerous oscillations following. The sea covered most of the land west of the Mississippi. In Europe a clear sea stretched from inland to central Germany at the beginning of Carboniferous time, but later this area was a series of swamps. In Russia the land, after several changes of level, sank, and a great area, comprising southern Europe and Asia and part of northern Africa, was covered by the sea. The plant-life of the Carboniferous Period - entirely gymnosperms and angiosperms showed some advances from the Devonian. The ferns were most abundant, some being like tall trees, others as small the maidenhair fern of to-day. The most conspicuous growths in the Carboniferous forests the Lycopods or club-mosses, sented by insignificant forms, but then growing sometimes 75 feet or more high, with trunks three feet in diameter, and spreading branches (Lepidodendron). Other Lycopods (Sigillaria) had short, thick trunks with few if any branches. Still another group of cryptogams, the Equiseta or horse-tail rushes, were of far greater importance in Carboniferous time than now. Of these the calamites, with their tall, slender stems, must have been one of the commonest plant forms of the Carboniferous forest. No plants with conspicuous flowers existed, the flowering plants being gymnosperms of which one of the commonest was Cordaites. The Carboniferous forests were probably gloomy and featureless. The singularity of the flora over the whole world from Siam to Spitzbergen indicates a uniform climate without temperature zones.

as

were now repre

Of animal life, corals, especially the genus Lithostrotion, were abundant; and the Foraminifera, especially the genus Fusulina, became of importance. Of the echinoderms the extinct blastoids, particularly the genus Pentremites, were abundant, and the Carboniferous is the period in which the crinoids, or sea-lilies, reached their highest development. Sea-urchins (echinoids) were more plentiful than in the Devonian, but the trilobites were slowly dying out. Of the land arthropods, scorpions were fairly abundant, and the first true spiders appeared. The brachiopods were less abundant than in the Devonian, the genus Productus being of most importance. Bivalve mollusks were numerous, among them being the first land shell. Of the fishes, the sharks, notably the orders Pleuracanthus and Acanthodes, were remarkably developed. Amphibians, which probably existed in

Devonian, increased greatly in Carboniferous time, but belonged to an order now extinct, Stegocephala, and were of small or moderate size, no species being over eight feet long.

Carboniferous System. As the rocks laid down in Carboniferous time furnish by far the greater part of the world's supply of coal, they have been very carefully studied in many different places and accurately mapped, so that more is known of the Carboniferous rocks than those

of any other Palæozoic system. By American geologists the rocks are divided into two series, an upper and a lower, which differ greatly in Nova Scotia, the Appalachian States, the Mississippi valley, and the Rocky Mountain States.

The Lower Carboniferous series, in what is called the Acadian province, Nova Scotia, and New Brunswick, is made up of thick beds of sandstone and limestone overlaid by limestones containing masses of gypsum. The total thickness of the series is 6,000 feet. In Pennsylvania the Lower Carboniferous series is divided into the Pocono sandstone and the Mauch Chunk shales, with a total maximum thickness of 4,000 feet. Westward there are in Ohio the Waverly beds, shales with some limestone, and in Michigan the marshall beds, sandstone and gritty shales, with limestone and gypsum above. Farther west the Lower Carboniferous is represented by the Mississippian series, including the Kinderhook, Osage, St. Louis, and Chester stages, all limestones, with a maximum thickness of over

1,200 feet in southern Illinois. These limestones underlie the eastern and western interior coal fields (see COAL). In southwestern Virginia are limestones, sandstones, and shales of Lower Carboniferous age, 2,000 feet thick, and containing a few workable beds of coal. In the Rocky Mountains the Lower Carbonifer-ous rocks are, with few exceptions, limestones.

The rocks of the Upper Carboniferous include the great coal fields of eastern North America. (For the origin of coal fields, seeCOAL.) The rocks of the coal measures are sandstones or conglomerates, grits, shales, clays, limestones, and seams of coal. A coal seam is usually underlaid by a bed of fire-clay, representing an old soil, and overlaid by shale. The total thickness of the Nova Scotia coal measures is 7,000 feet, and 76 distinct seams of coal are known. In Pennsylvania the coal measures. have been separated into the millstone grit, lower productive, lower barren, and upper productive stages, and have a total thickness of 4,000 feet. In Michigan the coal measures are about 300feet thick; in the eastern interior (IllinoisIndiana) field 600 to 1,000 feet, and in the western interior field the thickness varies widely,. reaching a maximum in Arkansas.

The Upper Carboniferous rocks cover wide areas in Utah, Colorado, and Arizona; they also. occur in the Black Hills in South Dakota, and in California, and British Columbia. They are generally limestones or sandstones, and contain no coal beds. The distinction between Upper and Lower Carboniferous is not as sharp as in the Mississippi valley. The total thickness of the whole Carboniferous series in Nevada and Utah is about 13.000 feet.

In western Europe the Lower Carboniferous. limestones reach from Ireland to central Germany, with a maximum thickness in England of 6,000 feet. In southeastern Germany the Lower