396 
Canaigre. 
/Am.  Jour.  Pharm. 
\      August,  1889. 
ered  in  July,  1874.  He  found  23*16  per  cent,  tannin,  and  proved 
the  presence  of  chrysophanic  acid  and  aporetin.  He  was  not  aware 
of  the  botanical  origin  of  the  plant,  but  supposed  it  to  belong  to  the 
natural  order  Polygonaceae. 
In  1879,  Mr.  Wm.  Saunders1  in  his  report  on  canaigre  stated  it 
was  the  Rumex  hymenosepalum  of  Torrey,  and  furnished  a  lithographic 
plate  of  the  plant  in  bloom. 
At  the  New  Orleans  Exposition,  1885-86,  in  one  corner  of  the 
section  devoted  to  products  from  New  Mexico  were  some  of  these 
roots,  above  which  was  the  inscription,  "  A  new  tanning  material." 
As  will  be  shown  later,  this  exhibit,  insignificant  as  it  appeared, 
attracted  the  attention  of  at  least  one  person. 
In  1886 2,  a  sample  of  a  root  sent  to  me  from  San  Antonio,  Texas, 
under  the  name  of  "  Indian  Root,"  was  analyzed  and  the  results 
published  under  the  title  of  "  Yerba  del  Indio,"  from  the  im- 
pression it  was  the  Aristolochia  foetida  of  the  Mexican  Pharmaco- 
poeia. This  impression,  however,  was  corrected  by  Professor  J.  M. 
Maisch  in  the  same  issue,  page  115.  He  suggested,  and  it  has  since 
been  found  to  be  correct,  that  this  "  Raiz  del  Indio  "  was  the  canai- 
gre root.  That  analysis  fixed  the  amount  of  tannin  at  11*66  per 
cent.,  but  it  was  found  that  the  root,  which  was  not  analyzed  as  soon 
as  received,  had  commenced  to  decay  and,  later,  it  was  completely  rid- 
dled by  insects.  In  this  respect  my  experience  differed  from  that  of 
the  Government  chemist,  who  found  no  change  after  ten  years. 
Soon  after  the  New  Orleans  Exposition  samples  of  two  or  three 
hundred  pounds  were  sent  to  Chicago  for  experiments  in  a  number  of 
tanneries  there.  Mr.  E.  C.  Denig  of  that  city  has  devoted  much 
time  since  then  to  studying  this  material,  from  its  source  in  Texas 
and  New  Mexico  to  its  application  in  the  tanning  of  hides. 
Canaigre  consists  of  heavy  globular  and  fusiform  pieces  from  two 
to  six  inches  long  and  one  to  three  inches  in  diameter.  Externally 
it  is  of  a  dark,  reddish-brown  color,  becoming,  by  age,  almost  black ; 
internally  it  is  from  a  bright  to  a  brownish-yellow  according  to  age 
and  amount  of  exposure  to  atmosphere.  When  collected  the  roots 
consist  of  clusters  resembling  sweet  potatoes.    They  are  found  near 
the  surface  or  sometimes  on  top  of  the  ground,  are  rapidly  dried  and,  at 
.  :  i  
1  Keport  of  the  Commissioner  of  Agriculture,  1879,  p.  364. 
2  An  Analysis  of  Aristolochia  foetida.  American  Journal  of  Pharmacy,  1886, 
p.  113. 
