432 
Investigation  of  the  Tannins. 
/Am.  Jour.  Pliar m. 
I  September,  1900. 
EUPHORBIACE^E. 
Jatropha  Cardiophy lla.—  A  supply  of  the  roots  and  stems  of  Jatro- 
pha  cardiophy  lla,  Muell.,  was  received  from  Prof.  J.  W.  Tourney  on 
March  4,  1896.  This  gentleman  also  sent  the  following  description: 
"An  abundant  shrub  on  the  dry  foothills  of  southern  Arizona  and 
Sonorse.  You  will  observe  the  beautiful  rich  color  of  the  root  and 
stems.  This  color  I  am  told  is  imparted  to  the  leather  in  tanning. 
This  plant  is  probably  the  most  abundantly  used  by  the  Indians 
and  Mexicans  for  the  purpose  ot  tanning  of  any  of  our  native  plants. 
It  has  the  reputation  of  producing  an  exceedingly  fine  leather  of 
superior  quality.  The  plant  is  known  to  the  Mexicans  as  '  Sangre 
de  Drago.'  "  An  estimation  of  the  material  showed  the  following 
percentages : 
Rhizophorece. — The  following  mangrove  barks  were  received  from 
Dr.  H.  N.  Ridley,  of  the  Botanic  Gardens  at  Singapore,  who  wrote 
as  follows :  "  The  mangrove  barks  I  sent  all  grow  in  the  .mangrove 
swamps,  and  all  but  Carapa  belong  to  the  Rhizophoreae.  Carapa  is 
a  Meliaceae.  The  mangrove  swamps  consist  of  tidal  mud,  covered 
with  a  thick  growth  of  the  trees  which  I  sent  the  bark  of ;  to  which 
may  be  added  Aircennia  and  the  Sonneratias  and  Heritiera.  There 
is  little  else  there  excepting  epiphytes  on  the  mangrove  trees. 
Nearly  all  these  trees  contain,  or  may  be  expected  to  contain,  tannin, 
which  no  doubt  protects  them  from  injury  by  the  sea  water.  But 
the  only  ones  used  for  tanning  are  those  I  sent  you.  Indeed,  Carapa 
is  not  used  in  this  way,  but  as  an  astringent  for  dysentery.  Ceriops 
is  considered  far  the  most  valuable  for  tanning,  and  in  addition  is 
used  for  dyeing  cloth." 
The  barks  have  the  following  names,  and  are  from  the  respective 
sources : 
Akit,  Rhizophora  conjugata. 
Tumu,  Bruguiera  rheedii. 
Lenggadi,  Bruguiera  parviflora. 
Supsup,  Sumnitzera  coccinea. 
Belukop,  Rhizophora  mucronata. 
Tengah,  Ceriops  candolleana. 
Bosing,  Bruguiera  caryophylloides. 
Nirch,  Carapa  mollucana. 
Per  Cent. 
Moisture  
Ash  in  absolutely  dry  .  . 
Tannin  in  absolutely  dry 
7*12 
4'95 
5'27 
