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        How was Mount




        Rushmore made?



         The explosive methods used to ccuve these stony-faced presidents into the granite

              he ultimate symbol of American   this was during America's Great Depression, a   So that's the main structural sculpting taken
              democracy, the Mount Rushmore   time when a lot of people were just thankful to   care of, now for the less explosive techniques.
         T  National Memorial has presided over the   have jobs.              Men were lowered down in front of the 500-foot
         Black Hills of South Dakota since its completion   A massive 90 per cent of the rock removed from   rock face in bosun's chairs, using thick steel
         in 1941. The sculpture, depicting 6o-foot effigies   the mountain was blown away using dynamite.   cable. At the top of the mountain, men in winch
         of presidents George Washington, Thomas   The powdermen in charge of the explosives set   houses controlled and lowered the cables by
         Jefferson, Theodore Roosevelt and Abraham   different-sized charges in specific locations in   hand. If they winched too quickly, the workers
         Lincoln, was designed by American sculptor   order to remove exact amounts of rock.   in the bosun's chairs would be injured, and so
         Gutzon Borglum, who sadly passed away before                         call boys were employed to sit on the mountain
         the memorial was actually finished.   A massive 90 per               edge and shout instructions to the winch men.
          On a happier note, of the 400 workers                                To sculpt the last six inches of stone, drillers
         involved in carving these iconic figureheads,   cent of the rock removed   and carving assistants used jackhammers and a
         none died during the mammoth undertaking ­  from the mountain        technique called honeycombing, whereby they
         unusual for any construction of the time, let                        bored holes very close together. This weakened
         alone one involving dynamite and at such   was blown away            the hard granite so that it could be finished off
         dangerous heights. In fact these workers even                       by hand and then the presidents' faces were
         had to climb a mountain to get to work, but then  using dynamite     smoothed off using 'bumping' tools. 0

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