Am.  Jour.  Pharm  ) 
Oct.,  1879.  f 
Notes  on  Cinchona  Bark. 
natural,  mossed  and  renewed  from  trees  planted  each  year  from  1863 
to  1867. 
As  "  natural  "  bark  from  the  lower  stems  is  only  obtained  from  trees 
not  yet  treated  for  "  renewing,"  it  is  evident  that  in  the  older  planta- 
tions the  natural  bark  will  be  chiefly  from  the  upper  stem  or  from 
saplings  and  inferior  trees,  and  thus,  as  Dr.  De  Vrij  has  shown,  will 
be  of  inferior  quality. 
The  result  shows  this  to  be  the  case,  the  best  parcel  of  natural  bark 
being  from  the  plantation  of  1867,  that  from  the  other  plantations 
being  of  uneven  quality,  showing  no  regular  variation.  The  mossed 
bark  on  the  other  hand  may  fairly  be  taken  to  represent  the  oldest  bark 
from  the  main  stems  in  each  plantation,  and  therefore  is  the  best  guide 
as  to  the  influence  of  age  on  the  quality  of  the  bark. 
The  result  is  highly  satisfactory,  showing  that  as  yet  the  bark  from 
the  oldest  plantations,  so  far  from  deteriorating,  continues  to  improve. 
Both  the  quinia  and  the  total  crystallizable  alkaloid  steadily  increase 
from  the  bark  of  the  1867  plantation  to  that  of  1864,  that  of  the  1863 
plantation  yielding  the  same  quinia  as  that  of  1864,  and  slightly  more 
•cinchonidia  and  quinidia. 
It  is  certainly  more  likely  that  so  regular  a  progression  is  the  result  of 
greater  maturity  than  that  the  difference  should  be  caused  by  any  variety 
in  the  C.  officinalis  cultivated. 
This  is  a  most  important  point,  for  recent  importations  of  the  bark 
of  C.  succirubra  confirm  the  opinion  so  often  expressed  by  my  uncle, 
J.  E.  Howard,  F.R.S.,  and  by  Mr.  Broughton,  the  late  Quinologist  to 
the  Indian  Government  ("  Quinology  of  the  East  Indian  Plantations," 
p.  71),  that  in  this  species  the  bark  deteriorates  beyond  a  certain  age. 
It  is  difficult  to  say  exactly  what  that  age  may  be,  and  it  probably  varies 
according  to  the  growth  of  the  tree,  but  some  of  the  very  finest  of  the 
red  bark  now  coming  from  India,  as  far  as  appearance  goes,  certainly 
seems  to  have  passed  its  maximum  of  richness  in  quinia. 
As  to  the  "renewed"  officinalis  bark,  the  time  during  which  the 
different  parcels  have  been  forming  is  not  given,  nor  is  it  stated  whether 
it  is  from  the  first,  second  or  later  crops,  and  therefore  the  comparison 
may  not  be  accurate  ;  but  it  is  interesting  to  see  that  here  also  the  older 
plantations  show  no  deterioration,  the  best  being  from  the  1863  planta- 
tion. 
From  a  private  plantation  I  have  received  a  sample  of  root  bark  of 
