COAST-DEFENSE                                           4^5                                                             COBALT

duction of soft coal. Named in the order of their gross product in 1906, the chief coal-producing states are as follows:

Pennsylvania 201,672,557 (of which 72,139,566 were anthracite); West Virginia 46,452,000; Illinois 38,317,581; Ohio 27,213,495; Alabama 12,851,775; Indiana 11,422,000; Colorado 10,358,421 (50,000 tons being anthracite). The states that produced from ten to one million tons, down, in the order named, were Kentucky (9,740,720), Iowa (7,017,485), Tennessee (6,210,000), Kansas (6,010,858), Wyoming (5,805,322), Maryland (5,014,995), Virginia (4,546,040), Missouri (3,860,000), Washington (3,293,098), Indian Territory (2,980,600), New Mexico 1,993,658, (anthracite yielding 20,000 tons), Arkansas (1,875,569), Utah (1,839,219), Montana (1,787,934), Michigan (1,370,060) and Texas (1,290,600). States producing less than 1,000,000 tons were Georgia and North Carolina together (363,-4Ŏ3), North Dakota (300,998), Alaska and Nevada (90,000), California (80,000) and Oregon (79,731). The bituminous production was 341,629,113 short tons, the anthracite tonnage 72,209,566. Their value was $566,857,953. (In 1907 Illinois yielded 51,317,146 short tons of soft coal, West Virginia 48,092,583).

The chief coal-producing countries outside of the United States are those mentioned in the general table. To this list should perhaps be added India, Nova Scotia and Spain. R. D. Salisbury.

Coast-Defense. In 1885 the nation awoke to the fact that the fortifications that should protect our cities and prevent a foe from using our harbors as bases of warlike "operations were absurdly weak— in many cases not strong enough to keep out a single line of battleships. Our navy had just been born, and we were without torpedo or other coast-defense vessels. In 1886 about 100 million dollars were appropriated to be spent in 10 years for coast defense; but for many years the matter was greatly neglected. To-day, however, it is believed that our principal ports and harbors are safe from any attack from the sea, even if our navy were driven from the ocean. The defences on the great lakes are comparatively weak, as our treaties with Great Britain prevent either country from maintaining more than a few small vessels upon these waters. The first plans for coast-defense relied largely on vessels of great gun-power and lying very low in the water, so as to offer a small target. These ships were expected to remain in the harbor to supplement the forts. But this type of harbor-defense is abandoned. The coast-defense forts are to all appearance nothing but grassy mounds of earth. The guns for the most part are of the disappearing type, presenting a target to the enemy only at the moment of firing. The

latest form of coast-defense is the submarine ship of which we already have a few.excellent examples.

Coast Range, a mountain range in California, extending from the Oregon boundary into Lower California. It is 30 to 40 miles wide, and is divided by the Bay of San Francisco. From the main range spurs reach out to the coast line, inclosing fertile valleys. The most noted are the Los Angeles, Santa Clara and Sonoma valleys. The highest peak is Mt. San Bernardino, 11,600 feet in height.

Coast-Survey, of the United States, is an undertaking of great importance. With a long and dangerous seacoast; with thousands of vessels yearly entering and leaving our ports; and with a great coasting trade, it is the duty of the nation to provide every means which science and skill can offer for pointing out the dangers of the coast. The coast-survey was founded for these objects. It furnishes accurate maps of the whole coast, including Alaska; it points out the site of, or suitable places for, lighthouses and beacons; it traces the ocean-currents along the shores; it studies the tides; it finds out the courses of the winds, the changes which take place at the entrance to harbors, the character of the bottom of the sea off the coast, etc. The first suggestion in the way of organizing a coast-survey was made in Jefferson's message to Congress in 1807; but work was not commenced until 1817. The large scope of the work, its accuracy, the quickness and cheapness with which results have been reached—taking much less time and costing much less than the British survey— have been largely due to its long-time superintendent, the late .Prof. A. D. Bache. Besides the valuable scientific knowledge gained, many discoveries of great value to commerce have been made. Thus the entrance to Delaware Bay was found to be eight miles in error. Six dangerous shoals were found in one year near Nantucket, right in the track of trans-Atlantic ships and of the heavy coast-trade between the eastern and the southern states. A new channel, with two more feet of water than any other, was discovered in New York harbor. The reports on the tides and the Gulf Stream were also of the greatest value to commerce.

Co'bait. This chemical element has an atomic weight of 59. Its symbol is Co. It is a metal, very tenacious, but not commercially valuable except as the basis of certain brilliant paints, sometimes referred to as cobalt green and cobalt blue. It is often used to color glass blue and in the making of blue porcelains, etc. These colors are derived from the oxides of cobalt. The chloride of cobalt may be used as. a sympathetic ink, i.e., an ink which can be made to appear or disappear; for, when