CURE - To alter industrially, a? to vulcanize (rubber), or to treat (synthetic 

 resinsl with heat or chemicals to make infusible. 



CURRENT - A flow of water. 



CURRENT, LITTORAL - Any current in the littoral zone caused primarily by 

 wave action, e.g., longshore current, rip current. 



DAP - A notch cut in one timber to receive another, usually permitting the 

 two timbers to be flush. 



DATUM, PLANE - The horizontal plane to which soundings, ground elevations, 

 or water surface elevations are referred. The plane is called a TIDAL 

 DATUM when defined by a certain phase of the tide. The following datums 

 are ordinarily used on hydrographic charts: 



MEAN LOW WATER - Atlantic coast (U.S.), Argentina, Sweden, and Norway; 



MEAN LOWER LOW WATER - Pacific coast (U.S.).; 



MEAN LOW WATER SPRINGS - United Kingdom, Germany, Italy, Brazil, 



and Chile; 

 LOW WATER DATUM - Great Lakes (U.S. and Canada); 

 LOWEST LOW WATER SPRINGS - Portugal; 

 LOW WATER INDIAN SPRINGS - India and Japan; 

 LOWEST LOW WATER - France, Spain, and Greece. 



A common datum used on topographic maps is based on MEAN SEA LEVEL. 



DENIER - A unit expressing the fineness of silk, rayon, nylon or other 

 synthetic yarns in terms of weights in grams per 9 000 meters of length. 



DEPTH - The vertical distance from a specified tidal datum to the sea floor. 



DIKE (DYKE) - A wall or mound built around a low-lying area to prevent 

 flooding. 



DOLPHIN - A cluster of piles. 



DUNES - (1) Ridges or mounds of loose, wind-blown material, usually sand. 

 (2) BED FORMS smaller than bars but larger than ripples that are out of 

 phase with any water-surface gravity waves associated with them. 



DURABILITY - A relative term for the resistance of a material to loss of 

 physical properties or appearance as a result of wear or dynamic operation. 



ELONGATION AT FAILURE - The length of a fabric test specimen when it is 

 broken in a tensile test (ASTM D1682-6.41 compared to its original length, 

 expressed as a percent. 



EMBANKMENT - An artificial bank such as a mound or dike, generally built 

 to hold back water or to carry a roadway. 



ENDEMIC - Native to a specific geographic area. 



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