COASTAL PLAIN 



1449 COAST AND GEODETIC SURVEY 



world's coal-tar dye industry. Although coal 

 tar was made in all civilized countries and 

 distilled in many, it was only in Germany that 

 the nine chief substances obtained directly by 

 distillation were converted into the 270 derived, 

 or "intermediate," substances, from which in 

 turn the 900 or more different coal-tar dyes then 

 in use were made. About three-fourths of the 

 world's supply of finished dyes was made in 

 Germany. The other fourth was finished in 

 other European countries and in the United 

 States, but from the intermediate substances 

 made in Germany. The outbreak of the war 

 caused great embarrassment to textile manu- 

 facturers, not only in the European countries 

 fighting Germany, but also in America, whose 

 supply was cut off by the allies' control of the 

 seas. The result was a great expansion of the 

 coal-tar dye industry in the United States and 

 Canada. J.F.S. 



COAST 'AL PLAIN, a stretch of lowland 

 extending along a seacoast, and sloping gently 

 toward the floor of the sea, of which it is a 

 continuation. Such a plain represents what in 

 many cases was formerly the bed of the sea, 

 and is composed of material washed down from 

 the mountains by rivers. This material, by a 

 gradual process of accumulation, builds up a 

 plain on the sea floor that grows higher and 

 higher until it becomes a part of the land 

 area of the continent. The action of the waves 

 tends to level the surface, and the plain in- 

 creases gradually in width as successive portions 

 of the sea floor are raised to the surface. As 



A NARROW COASTAL PLAIN 



soon as a plain is formed rivers begin to cut 

 channels in its surface, for coastal plains are 

 exposed to the same processes of weathering as 

 mountains and plateaus. Because of the com- 

 paratively-level surface, nearness to the sea, 

 fertile soil and navigable rivers, coastal plains 

 usually become prosperous centers of popula- 

 tion. Among well-developed coastal plains 

 of the world are those of Eastern North Amer- 



ica, the east coast of India along the Bay of 

 Bengal, the coastal slope of Guiana and the 

 plains of Patagonia, east of the Andes Moun- 

 tains. 



The Atlantic Coastal Plain is one of the 

 best examples of this type of plain. It lies 

 along the eastern shore of the North American 

 continent from Canada to Mexico, bordering 

 on the Atlantic Ocean and the Gulf of Mex- 

 ico. From New York to Georgia it occupies 

 a narrow strip of land between the Atlantic on 

 the east and the foothills of the Appalachian 

 Mountains on the west; below Georgia it 

 broadens out to include Florida. Passing 

 around the southern limits of the Appalachian 

 range in Northern Alabama, it widens out and 

 extends as far north as the Ohio River, while 

 a narrower strip west of the Mississippi River 

 extends south westward as far as Vera Cruz, 

 Mexico. 



The abrupt slope which marks the line along 

 which the older land and the coastal plain 

 merge is known as the "Fall Line" (which see). 



COAST AND GEODETIC, jeodet'ik, SUR- 

 VEY, a bureau of the United States govern- 

 ment which had its beginning as far back as 

 1807, when Congress, at the suggestion of Pres- 

 ident Jefferson, authorized the establishment 

 of the national coast survey as a bureau under 

 the Secretary of the Treasury. The Coast 

 Survey was actually organized in 1816, and the 

 first field work was done in that year, but little 

 actual work was accomplished before 1832. 

 In 1871 the scope of the bureau was enlarged 

 to furnish geographic positions and other data 

 for state surveys. In 1878 it became the Coast 

 and Geodetic Survey; it was transferred to the 

 Department of Commerce and Labor in 1903, 

 and to the Department of Commerce in 1913. 



Work of the Bureau. The Coast and Geo- 

 detic Survey operates under two divisions 

 field and office. The chief function of the field 

 force is charting the coasts of the United States 

 and its island dependencies. Some idea of the 

 magnitude of the task may be gathered from 

 the fact that while the general coast line of 

 the United States and Alaska is 11,500 miles 

 in extent and that of the Philippines, Hawaii. 

 Porto Rico, Guam and Tutuila 5,400 miles, 

 the actual shore line, which includes all the 

 islands, bays, sounds and rivers in the tidal 

 belt, is 103,000 miles 91,000 for the United 

 States and Alaska and 12,000 for the latter 

 group. The topographic work extends only 

 three to four miles from the coast, while the 

 ocean is charted put as far as necessary for 



