624  Powdered  Vegetable  Drugs.  {^SS^mt' 
be  a  light  tan  rather  than  a  dark  brown,  etc.  The  value  of  Taraxa- 
cum and  other  more  or  less  important  drugs  rich  in  reserve  mate- 
rials, as  inulin,  starch,  etc.,  may  be  ascertained,  as  these  reserve 
materials  are  contained,  no  doubt,  in  greatest  abundance  in  the  plant 
at  the  time  that  the  active  medicinal  agents  are  present  in  likewise 
greatest  amount. 
(2)  Certain  facts,  as  the  presence  of  pollen  grains  in  Chestnut 
leaves  will  cause  us  to  go  into  the  woods  and  study  the  ecological 
and  biological  relations  of  the  plants  which  yield  us  our  drugs. 
For,  without  this  study  upon  Nature  herself,  we  shall  never  know 
what  value  to  place  upon  such  observations  or  their  real  significance. 
(3)  The  presence  of  reserve  starch  in  leaves  and  a  diminution  in 
calcium  oxalate  in  any  part  of  the  plant  where  normally  it  is  pres- 
ent, will  cause  us  to  open  our  eyes  to  the  study  of  micro-organ- 
isms and  inquire  as  to  what  these  things  have  to  do  with  the  dete- 
rioration of  drugs  and  the  spoliation  of  medicinal  preparations. 
When  these  pharmacognostical  problems  are  understood  then  we 
will  cease  to  devote  our  energies  to  indiscriminately  mixing  certain 
things  together  in  our  attempts  to  make  elegant  pharmaceutical 
preparations,  but  will  start  out  to  know  what  causes  the  difficulty 
and,  knowing  this,  we  know  how  to  proceed  intelligently  and  in  a 
scientific  manner,  just  as  we  proceed  in  certain  chemical-pharma- 
ceutical work. 
(4)  The  use  of  the  microscope  in  the  examination  of  vegetable 
drugs  (whether  they  be  crude  or  powdered),  as  also  in  the  exami- 
nation of  animal  substances  and  chemical  compounds,  is  an  appli- 
cation of  this  instrument  to  a  degree  that  this  communication 
indicates — to  some  extent  at  least — the  widest  practical  application. 
In  fact,  it  opens  up  the  necessity  for  making  microscopical  exami- 
nations and  micro-chemical  tests  to  a  much  greater  degree  than 
heretofore  on  the  crude  as  well  as  powdered  drug. 
The  author  would  impress  again  upon  all  investigators  the 
necessity  for  accurate  measurements  of  tissues  and  contents  of 
materials  which  are  studied  ;  as  also  the  name  of  the  media  or 
reagent  in  which  the  specimen  lies  or  to  which  it  has  been 
subjected.  KOH,  chloral,  glycerin,  etc. — all  of  these  have  the 
property  of  affecting  the  thickness  and  character  of  the  cell  walls 
and  cell  contents,  and  it  is  upon  these  characteristics  that  we  must 
rely  for  our  useful  studies  of  crude  and  powdered  drugs. 
