﻿510 
  ANNUAL 
  EEPORT 
  SMITHSONIAN 
  INSTITUTION, 
  192 
  9 
  

  

  engineer, 
  showed 
  how 
  steam 
  could 
  be 
  used 
  to 
  obtain 
  the 
  vacuum. 
  He 
  

   also 
  invented 
  the 
  safety 
  valve 
  and 
  proposed 
  to 
  apply 
  steam 
  to 
  draw 
  

   water 
  from 
  mines, 
  to 
  shoot 
  bullets 
  from 
  cannon, 
  to 
  propel 
  boats, 
  

   and 
  to 
  do 
  many 
  other 
  things. 
  He 
  did 
  not 
  construct 
  any 
  practical 
  

  

  engines, 
  however, 
  and 
  came 
  no 
  nearer 
  than 
  his 
  predecessors 
  to 
  solving 
  

  

  the 
  problem 
  of 
  maldng 
  the 
  piston 
  move 
  up 
  and 
  down 
  continuously. 
  

  

  Necessity 
  produced 
  the 
  next 
  invention. 
  England 
  was 
  experiencing 
  

  

  more 
  and 
  more 
  trouble 
  keeping 
  water 
  out 
  of 
  her 
  coal 
  mines. 
  The 
  

  

  