406 
The  Tannin  of  Castanopsis. 
Am.  Jour.  Pharm. 
August,  1897. 
educated  pharmacist  that  the  receipts  far  outweigh  the  cost  and 
time.  The  light  in  the  sky  is  already  appearing,  the  clouds  are 
rising  higher  and  higher  on  the  mountain  side,  and  the  practical 
pharmacists  are  ascending  one  by  one  to  higher  flights  than  where 
they  rested  yesterday,  and  they  follow  those  who  it  sometimes  may 
seem  are  working  in  the  clouds,  yet  who,  nevertheless,  when  the 
light  shines,  are  seen  to  be  laboring  for  the  benefit  and  the  future  of 
pharmacy. 
THE  TANNIN  OF  CASTANOPSIS. 
By  Henry  Trimble. 
In  the  June  number  of  this  Journal,  p.  296,  attention  was 
called  to  the  presence  of  strontium  in  the  bark  of  several  species  of 
castanopsis  received  from  Dr.  H.  N.  Ridley,  of  the  Singapore  Botani- 
cal Gardens,  India.  These  barks  have  also  been  examined  for  tan- 
nin; and  the  results  are  now  tabulated  along  with  those  from  two 
species  of  oak  also  from  Singapore,  and  two  samples  of  the  one 
species  of  our  native  castanopsis,  C.  chrysophylla.  The  results  on 
one  sample  of  the  latter  were  published  in  the  Garden  and  Forest, 
8,  293,  July  24,  1895  >  tne  editor,  Professor  C.  S.  Sargent,  adding 
some  remarks  concerning  the  genus,  which,  by  reproduction  here, 
will  throw  additional  light  on  the  subject. 
As  is  well  known,  the  bark  of  Quercus  densiflora,  of  California,  is  popularly 
considered  the  most  valuable  tanning  material  produced  in  the  Pacific  States  of 
North  America.  This  oak  is  the  only  American  representative  of  a  peculiar 
group  of  trees  which  inhabit  southeastern  Asia,  and  are  intermediate  in  botanical 
characters  between  the  true  oaks  and  the  chestnuts. 
There  is  another  genus,  Castanopsis,  which  is  also  intermediate  between  the 
oaks  and  the  chestnuts,  and  also  of  southeastern  Asia,  but,  curiously  enough, 
with  a  single  representative  in  Oregon  and  California,  Castanopsis  chry- 
sophylla, a  very  beautiful  tree,  which  the  Californians  call  the  gold-leafed 
chestnut,  from  the  bright  golden  scurf  which  covers  the  lower  surface  of  the 
leaves.  Some  botanists  treat  Castanopsis  as  a  section  of  Castanea,  while  others, 
like  Dr.  King,  of  Calcutta,  who  made  a  special  study  of  the  genus,  although 
finding  no  very  good  characters  by  which  it  can  be  distinguished  from  one  of 
the  Asiatic  sections  of  Quercus,  maintain  the  genus  for  the  purposes  of  conve- 
nience. The  relationship  of  this  tree  to  Quercus  densiflora  on  one  hand,  and  to 
the  chestnut  on  the  other,  suggested  that  its  wood  and  bark  might  contain 
valuable  tanning  properties. 
The  result  of  a  comparison  of  the  American  Quercus  and  Castan- 
opsis, was  to  show  that  the  tannin  of  Castanopsis  chrysophylla  is 
