APPENDIX I GLOSSARY AGGREGATE—  Crushed  rock  or  gravel,  screened  to sizes  for  use  in  road  surfaces,  concrete,  or bituminous  mixes. ANGLING DOZER (Angledozer)—A  bulldozer  with  a blade that can be pivoted on a vertical center pin so as to cast its load to either side. APRON— The front gate of a scraper body. ASPHALT—  A  dark  brown  to  black  cementitious material  in  which  the  predominating  constituents are bitumens that occur in nature or are obtained in petroleum  processing.  Asphalt  is  a  constituent  in varying proportions of most crude petroleums. ASPHALT CEMENT— A fluxed or unfluxed asphalt specially  prepared  as  to  quality  and  consistency  for direct use in the manufacture of asphalt pavements. ASPHALT CONCRETE— High-quality thoroughly controlled  hot  mixture  of  asphalt  cement  and well-graded, high-quality aggregate, thoroughly compacted into a uniform, dense mass. ASPHALT LEVELING COURSE—  A  course  (asphalt aggregate mixture) of variable thickness used to eliminate irregularities in the contour of an existing surface   before   a   superimposed   treatment   or construction. ASPHALT,  MEDIUM-CURING  (MC)—  Cutback asphalt, composed of asphalt cement and a kerosene type of diluent of medium volatility. ASPHALT, RAPID-CURING (RC)— Cutback  asphalt, composed  of  asphalt  cement  and  naphtha  or gasoline type of diluent of high volatility. ASPHALT, SLOW-CURING (SC)—  Cutback  asphalt, composed  of  asphalt  cement  and  oils  of  low volatility. AUGER— A rotating drill having a screw thread that carries cuttings away from the face. AUXILIARY— A helper or standby engine or unit. AXIS OF ROTATION— The vertical line around which the  upper  structure  rotates. AXLE, LIVE— A  revolving  horizontal  shaft. BACKFILL—  (1) The material used in refilling a ditch or  other  excavation.  (2)  The  process  of  such refilling. BAIL BLOCK— Block attached to a dragline bucket, through which rope line is reeved. Also referred to as  “PADLOCK.” BAIL (BUCKET)— A yoke or spreader, hinged to the sides of a dragline bucket, to which is attached a connecting   sheave   or   chain   for   hoisting   and dragging  operations. BALL JOINT— A connection, consisting of a ball and socket, that will allow a limited hinge movement in any  direction. BANK—  Specifically, a mass of soil rising above a digging or trucking level. Generally, any soil that is to be dug from its natural position. BANK GRAVEL— Gravel  found  in  natural  deposits, usually  more  or  less  intermixed  with  fine  material, such as sand or clay, and combinations thereof; gravelly  clay,  gravelly  sand,  clayey  gravel,  and sandy gravel indicate the varying proportions of the materials  in  the  mixture. BASE COURSE— The layer of material immediately beneath the surface or intermediate course. It may be  composed  of  crushed  stone,  crushed  slag, crushed   or   uncrushed   gravel   and   sand,   or combinations of these materials. It also may be bound with asphalt. BANK YARDS— Yards of soil or rock measured in its original  position  (before  digging). BEDROCK—  Solid  rock,  as  distinguished  from boulders. BENCH— A working level or step in a cut that is made in several layers. BINDER— (1) Fines which hold gravel together when it is dry. (2) A deposit check that makes a contract valid. BITUMEN— A class of black or dark-colored (solid, semisolid,  or  viscous)  cementitious  substance, natural  or  manufactured,  composed  principally  of AI-1