CHEMICAL  ACCURACY. 
135 
tory  ?  Yes  ;  no  foul  air  must  touch  these  bodies.  Air,  that 
which  the  most  sensitive  persons  would  consider  sweet,  would  be 
poison.  The  slightest  trace  of  carbonic  acid  or  moisture,  things 
found  in  all  breezes,  would  make  some  analyses  imperfect.  We 
can  well  remember  when  in  that  stage  of  learning  when  sulphur 
and  hydrogen  are  so  much  employed  for  metals  we  rushed  for- 
ward to  seek  advice,  but  were  driven  back  from  the  sanctum  by 
the  usually  most  urbane  and  pleasant  friend.  What  could  that 
mean  ?  he  was  preparing  a  silver  salt  in  order  to  obtain  an  im- 
portant atomic  weight.  We  are  obliged  to  use  not  only  pure  air, 
but  sometimes  artificial  atmospheres,  and  sometimes  the  entire 
absence  of  atmosphere.  As  to  analysis  generally,  most  chemists 
have  seen  in  their  own  day  the  rise  of  the  methods  of  Fresenius. 
It  was  no  easy  matter  to  learn  from  that  of  Rose.  The  informa- 
tion was  great,  but  the  system  deficient.  Now  the  details  and 
system  of  Fresenius  seem  to  form  an  embodiment  of  logic  itself, 
and  if  any  one  learns  them  he  must  have  learned  to  reason  in 
such  a  way  that  he  will  gain  a  great  superiority  over  his  former 
self.  Every  step  carelessly  made  shows  itself  in  material  mis- 
takes ;  the  student  must  reason  closely  to  keep  his  solutions 
correct.  He  cannot  go  with  mere  enthusiasm  and  boasting  long. 
His  own  results  bring  him  the  greatest  reproaches,  his  experi- 
ments silently  humble  him,  and  he  is  laughed  at  by  forces  he 
cannot  avenge. 
We  sec  the  value  of  accurate  work  in  Berzelius  perhaps  more 
than  in  any  man.  He  built  up  inorganic  chemistry,  and  if  any 
man  follows  his  work  in  organic  departments  he  will  learn  to 
wonder  at  its  accuracy.  He  worked  as  if  the  eyes  of  posterity 
were  on  all  his  movements,  and  he  seemed  to  do  his  enormous 
labors  by  making  few  blunders.  There  is  no  chemist  from  whom 
the  young  can  learn  so  much  of  the  art  of  working  long  and 
honestly.  We  modify  his  structure,  but  it  was  said  by  one, 
himself  a  great  man,  "  Berzelius  is  the  greatest  chemist  that  is, 
or  that  was,  or  that  will  be." 
We  remember  sitting  with  an  old  philosopher,  when  he  said, 
"  Would  you  like  to  see  the  atoms  of  Epicurus,  out  of  which  the 
worlds  were  made — true  star-dust  ?"  Who  would  have  said  no  ? 
he  brought  a  little  bottle  of  metoniric  dust — but  we  must  not  de- 
