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Practice Reading: Fill in the Blanks (Dropdown) ID: #1213 Rudimentary elevators
Instructions
Rudimentary  elevators,  or  hoists,  were  in  use  during  the  middle  Ages  and  can  be  traced  back  to  the  third  century  BC.  They  were    by  animal  and  human  power  or  by  water-driven  mechanisms.  The  elevator  as  we  know  it  today  was  first    during  the  1800s  and  relied  on  steam  or  hydraulic  plungers  for  lifting  capability.  In  the  latter  application,  the  cab  was  affixed  to  a  hollow  plunger  that  lowered  into  an  underground  cylinder.  Liquid,  most  commonly  water,  was  injected  into  the  cylinder  to  create  pressure  and  make  the  plunger  elevate  the  cab,  which  would  simply  lower  by    as  the  water  was  removed.  Valves  governing  the  water  flow  were  manipulated  by  passengers  using  ropes  running  through  the  cab,  a/an    later  enhanced  with  the  incorporation  of  lever  controls  and  pilot  valves  to  regulate  cab  speed.  The  "granddaddy"  of  today's  traction  elevators  first    during  the  19th  century  in  the  U.K.,  a  "lift"  using  a  rope  running  through  a  pulley  and  a  counterweight  tracking  along  the  shaft  wall.

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