74 
THE  GUMS  AND  RESINS  OF  COMMERCE. 
state  that  one  Liverpool  firm  imported  in  three  years  Gum 
Senegal  to  the  value  of  £100,000.  Gums  to  the  value  of  3J 
millions  of  francs  have  been  shipped  annually  from  Alexandria. 
The  exports  from  Morocco  reach  to  250  or  300  tons,  and  India 
exports  1500  or  1600  tons. 
The  Gum  Arabic  of  commerce  is  the  produce  of  various 
species  of  acacia,  which  yield  this  substance  in  considerable  quan- 
tities, particularly  A.  vera,  a  native  of  Arabia,  and  of  Africa, 
from  Senegal  to  Egypt,  which  supplies  the  finest  qualities  ;  A, 
Arabica,  a  smaller  tree,  common  in  India  and  Africa,  which 
yields  part  of  the  Turkey  and  East  India  gum  ;  the  red  pieces 
constituting  the  gum  gedda  and  gum  babool  of  commerce. 
A.  gummifera,  a  high,  thorny  tree,  found  near  Mogador,  the 
coast  of  Guinea,  and  in  Arabia,  furnishes  what  is  known  as 
Barbary  gum,  a  darker  variety. 
A.  Senegal  yields  part  of  the  Senegal  gum,  the  tears  of  which 
are  usually  in  larger  masses  than  Arabic,  of  a  darker  color,  and 
more  clammy  and  tenacious.  The  trade  in  this  variety  is  chiefly 
in  the  hands  of  the  French,  and  we  have  imported  supplies  occa- 
sionally from  France. 
In  the  Cape  colony,  gum  is  collected  by  the  Kaffirs  from  a 
species  of  Acacia  closely  resembling  A.  vera,  which  Burchall,  in 
his  "  Travels  into  the  Interior,"  calls  A.  Capensis,  the  A.  Jcaroo, 
probably,  of  Hayne,  JSTies,  and  Ebermaier,  which  is  abundant  on 
the  banks  of  the  Orange  Biver.  It  is  of  a  pale  yellow  color, 
and  is  not  considered  by  the  dealers  so  good  as  that  obtained  in 
the  more  northern  parts  of  Africa. 
The  ordinary  Cape  gum  of  commerce  exudes  spontaneously 
from  the  bark  both  of  the  trunk  and  branches  of  the  thorn  tree 
(Acacia  horrida,  Willd). 
A  considerable  trade  was  carried  on  by  the  Cape  colonists  a 
few  years  ago  with  Kaffirland  for  the  gum  gathered  from  the 
Mimosa  tree.  Wagon-loads  were  constantly  being  sent  off  to 
Port  Elizabeth  for  shipment  to  the  London  market.  It  was  ex- 
tensively used  by  calico-printers,  calenderers,  makers  of  station- 
ery, and  in  various  industrial  arts.  The  exports  have  declined 
from  4S76  cwts.  in  1849,  to  72  cwts.  in  1853.  The  reason  for 
this  decline  is  curious.  By  mere  accident  it  was  discovered  that 
a  gum  could  be  manufactured  from  potatoes  or  wheat.  This 
