Am^TSPiKm'}        Structural  Plant  Relationships.  389 
symptomatic  condition,  unless  there  be  some  exceptional  counter- 
acting influence,  a  known  remedy  will  produce  specific  effects.  The 
method  by  which  all  this  is  determined  is  empirical ;  the  ultimate, 
when  established,  is  considered  a  phase  of  scientific  art. 
The  Demands  of  Science. — But  the  fact  soon  becomes  apparent 
that  medication  for  well-known  and  well-established  symptoms  is 
hazardous  if  one  depends  on  Nature's  varying  vegetable  crudities. 
As  the  husk  and  shell  of  plants  vary  their  proportions  to  other 
parts  of  the  plant,  under  the  influence  of  seasons,  sunshine  and 
showers,  likewise  do  the  proportions  and  relationships  of  the  inter- 
cellular structures  of  certain  parts  of  the  plants  used  in  medicine 
vary.  The  farmer  knows  that  one  season  a  field  of  grain  may  con- 
sist of  much  straw  and  little  oats,  while  the  next  year  the  grain  may 
be  heavy  and  the  stalk  light.  Nor  are  all  plants  in  a  crop  uniform. 
The  tree  that  bears  the  heaviest  load  of  foliage  may  be  barren  of 
fruit.  The  most  stately  cinchona  tree  may  be  covered  with  worth- 
less bark.  A  small  chestnut  tree,  loaded  with  fruit,  may  be 
overshadowed  by  a  mighty  chestnut  bearing  foliage  only.  This 
empiricism  teaches.  And  so  empiricism  or  observation  led  to  the 
first  attempt  to  make  more  uniform  preparations  from  the  crude 
parts  used  in  medicine.  Came  then  the  crude  extracts  both  fluid 
and  solid,  the  infusions  and  decoctions. 
Finally,  only  one  hundred  years  ago,  morphine  was  discovered. 
Quick  followed  quinine,  and  then  other  bodies  of  a  similar  nature. 
Now  entered  a  new  thought.  These  energetic  chemically-constructed 
ultimates  seemed  to  indicate  that  behind  every  natural  remedy  lay 
a  definite  something  that  could  replace  in  therapy  the  parent  struc- 
ture. This  one-sided  conception  held  the  thought  and  experiment 
of  many  talented  men  for  a  hundred  years,  it  locks  many  to-day  in 
its  tenacious  embrace  and  which  has  been  carried  by  some  to  irra- 
tional extremes.  That  it  was  a  natural  line  for  enthusiasm  to  take 
is  apparently  supported  by  the  aggressive  energies  of  a  few  educts 
and  products,  such  as  the  cathartic-  resins  of  jalap  and  podophyllum 
(which  are  in  themselves  complex  structures),  the  energetic  alkaloids, 
and  a  few  other  products  which  possess  in  themselves  qualities  to 
remind  one  of  the  parent  structures.  Thus  it  is  that  the  conspicuous 
example,  quinine  and  morphine,  nearly  one  hundred  years  ago  led  to 
blanket  theories  (resinoids  and  alkaloids)  which  well  nigh  wrecked 
the  Eclectic  school  half  a  century  later,  and  which  now  distract  and 
