rochleder's  proximate  analysis. 
469 
Whatever  relates  to  the  place  in  which  a  constituent  exists  is  certainly 
not  a  chemical  question,  even  when  it  lies  in  the  nature  of  things  that 
with  chemical  assistance,  or  perhaps  alone,  or  at  least  more  easily 
and  certainly  than  without  such  assistance,  this  question  can  be  an- 
swered. 
In  physiology,  in  geology,  and  other  sciences,  there  is  an  abundance  of 
problems  which  only  those  are  in  a  position  to  solve  who  possess  a  cer- 
tain sum  of  chemical  knowledge.  On  this  account,  these  problems  are 
merely  physiological  or  geological  ones,  and  the  physiology  or  geology  is, 
on  this  account,  no  chemistry,  although  when  not  studied  with  chemical 
knowledge,  they  are  less  essentially  advanced.  When  the  chemist  takes 
the  arithmetical  mean  of  the  results  of  three  elementary  analyses,  he  is 
not  necessarily  an  arithmetician,  although  he  must  have  learnt  to  calcu- 
late to  perform  this  operation  ;  and  when  a  chemist  arrives  at  the  remarka- 
ble idea  of  calculating  the  mean  of  his  analysis  according  to  the  method  of 
the  smallest  quadrate,  nevertheless  he  is  not  a  mathematician.  The  mineral- 
ogist is  not  a  chemist  when  he  tests  a  mineral  with  the  blowpipe. 
To  return  to  the  microscopic  examination  with  the  aid  of  reagents.  It 
will  be  self-evident  that  it  can  only  be  undertaken  when  a  correct  qualita- 
tive analysis  has  already  been  performed  with  the  material  under  exami- 
nation, and  the  behaviour  of  the  individual  constituents  with  reagents  has 
to  be  inquired  into  with  exactness.  It  is  also  self-evident  that  we  cannot 
conduct  an  examination  of  that  kind  with  live  or  six  reagents,  as  some 
persons  still  appear  to  consider  at  the  present  day.  We  must  have  confi- 
dence in  the  idea  that  we  must  test  under  the  microscope  in  the  same  man- 
ner as  without  it.  No  one  believes  that  simpler  methods  are  employed  in 
such  chemical  analysis,  and  that  several  reagents  can  be  used  when  spec- 
tacles are  worn.  But  a  microscope  is  nothing  else  than  spectacles  which 
permit  us  to  observe  things  which  we  are  not  able  to  see  with  our  naked 
eyes  on  account  of  their  smallness ;  it  saves  us  chemical  operations  and 
chemical  reagents  quite  as  little  as  the  spectacles  of  a  short-sighted  or 
long-sighted  chemist  are  in  a  position  to  spare  him  such  things.  What  we 
see  under  the  microscope  with  the  aid  of  reagents  is  only  understood  when 
we  have  been  able,  by  a  previous  analysis,  to  know  with  precision  the  con- 
stituents. Whoever  endeavors  to  learn  anything  under  the  microscope 
with  the  aid  of  reagents  without  a  previous  analysis  and  without  a  prelim- 
inary study  of  the  constituents,  is  like  a  man  who  strives  to  read  a  book 
which  is  written  in  a  language  unknown  to  him,  and  therefore  unintelli- 
gible to  him  with  the  assistance  of  lens.  The  result  is  precisely  the 
same.  He  will  know  as  little  after  the  labor  has  been  done  as  he  did  be- 
fore the  commencement.  The  vegetable  anatomist  is  quite  right  when  he 
endeavors  to  accomplish  his  object  by  the  application  of  some  few  reagents, 
and  facilitates  and  renders  possible  his  observations,  because  by  a  few 
chemical  agents  he  makes  certain  outlines  appear  more  defined,  or  compels 
