
 
		proposed  to  apply  the  heat  o f ascending  springs  
 to  the warming  o f green  houses.  Artesian wells  
 have  long  been  used  in  Italy,  in  the  duchy  o f  
 M od en a ;  they  have  also  been  successfully  applied  
 in  Holland,  China,* and N. America.  B y   
 means  o f  similar wells,  it  is  probable  that water  
 may  be  raised  to  the  surface  o f many  parts  o f  
 the  sandy  deserts  o f A frica  and Asia,  and  it  has  
 been  in  contemplation  to  construct  a  series  o f 
 *  An  economical  and  easy method  of sinking  Artesian Wells  
 and  boring for  coal, &c, has  recently  been  practised  near Saar-  
 bruck,  by M.  Sellow.  Instead  of  the  tardy  and  costly  process  
 o  oring with a number of Iron  Rods  screwed to  each  other,  one  
 heavy  Bar  of  cast  Iron  about six  feet  long  and  four  inches  in  
 diameter,  armed  at  its lower end with  a  cutting Chisel,  and surrounded  
 by  a  hollow  chamber,  to  receive  through  valves,  and  
 bnng up  the  detritus  of the perforated stratum, is suspended from  
 the  end  of  a  strong  rope,  which  passes over a wheel  or  pulley  
 xed  above  the  spot  in which  the hole  is  made.  As  this  rope  
 is  raised  up  and down  over  the  wheel,  its  tortion  gives  to  the  
 Bar of Iron  a  circular motion,  sufficient  to vary  the place  of  the  
 cutting Chisel  at  each descent. 
 When  the  chamber  is  full,  the  whole  apparatus  is  raised  
 quickly  to the  surface  to be  unloaded,  and  is  again  let  down  by  
 the  action  of the  same wheel.  This process has  been  long practised  
 in  China,  from  whence  the  report  of  its  use  has  been  
 rought to  Europe.  The Chinese  are said  to  have  bored  in  this  
 manner to the depth  of  1000  feet.  M.  Sellow  has  with this instrument  
 lately  made  perforations  18  inches  in  diameter,  and  
 several  hundred  feet  deep,  for  the  purpose  of  ventilating  coal  
 mines  at  Saarbruck.  The  general  substitution  of this method  
 for  the  costly  process  of  boring with  rods  of  iron,  may  be  of  
 much  public  importance,  especially  where  water  can  only  be  
 obtained  from  great depths.  J 
 these  wells  along  the  main  road  which  crosses  
 the  Isthmus  of Suez. 
 I  have  felt  it  important  thus  to  enter  into  the  
 theory  o f  Artesian  Wells,  because  their  more  
 frequent  adoption  will  add  to  the  facilities  of  
 supplying  fresh Water  in  many  regions  o f  the  
 Earth,  particularly  in  low  and  level  districts,  
 where this prime necessary o f Life  is  inaccessible  
 by  any  other means ;  and  because  the  theory  o f  
 their mode  o f  operation  explains  one  of the most  
 important and most  common  contrivances  in  the  
 subterraneous economy  o f the Globe, for the  production  
 o f natural  springs. 
 B y   these  compound  results  o f the  original  disposition  
 o f the strata  and their  subsequent disturbances, 
  the  entire Crust  o f the E arth has become  
 one grand and connected Apparatus o f Hydraulic  
 Machinery, cooperating incessantly with  the  Sea   
 and  with  the Atmosphere,  to  dispense  unfailing  
 supplies  of  fresh Water  over  the  habitable  surface  
 o f the  Land.* 
 Among  the  incidental  advantages  arising  to  
 Man  from  the  introduction  of  Faults  and  Dislo cations  
 of  the  strata,  into  the  system  o f  curious  
 arrangements  that  pervade the subterranean eco- 
 *  The  causes  of  intermitting  Springs,  and  ebbing  and  flowing  
 wells,  and  many  minor  irregularities  in  the  Hydraulic  Action  
 of natural vents of water,  depend on  local Accidents, such  as  the  
 interposition  of Syphons, Cavities, &c., which  are scarcely of sufficient  
 importance  to  be  noticed,  in  the  general  view we are  here  
 taking of the Causes of the Origin  of Springs.