Am.  Jour.  Pharm. 
Jujie,  1899. 
Classification  of  Gums, 
273 
SECTION  V.  OLEO-RESINS. 
Plant  exudations  consisting  of  resin  mixed  with  volatile  oil  in 
various  proportions ;  the  resin  frequently  being  dissolved  in  the  lat- 
ter, forming  a  liquid. 
Sub-section  1.  Lacquer  Group. — This  group  includes  the  natural 
varnishes  and  desiccating  lacquers,  which  have  the  property  of  dry- 
ing  hard  with  considerable  lustre.  They  are  mainly  yielded  by 
trees  belonging  to  the  order  Anacardiaceae. 
Examples:  Chinese,  Japanese,  Burmese  and  Indian  lacquers  and 
cardol. 
Sub-section  2.  Copaiba  Group, — These  are  fragrant  liquids, 
usually  classed  with  the  balsams,  but  which  differ  from  them  in  con- 
sisting of  a  comparatively  small  amount  of  resin  dissolved  in  volatile 
oil. 
Examples:  Copaiba  balsam  and  gurjun  balsam  or  "  wood-oil." 
Sub-section  3.  Turpentine  Group. — This  group  includes  the  soft 
resins  containing  more  or  less  volatile  oil,  which  are  exuded  by  the 
cone-bearing  trees. 
Examples:  Crude  turpentine,  Canada  balsam,  "  gum  thus,"  gali- 
pot, etc. 
Subsection  4..  Elemi  Group. — These  are  soft  resins,  seldom  con- 
taining more  than  10  per  cent,  of  volatile  oil.  They  are  mainly 
yielded  by  trees  belonging  to  the  order  Burseracese. 
Example :  Manila  and  Brazilian  elemi,  Mexican  "  copal,"  Carana 
resin  and  tacamahac. 
SECTION  VI.     TRUE  BALSAMS. 
Plant  exudations  consisting  of  resin  mixed  with  aromatic  acids, 
alcohols  and  esters. 
Examples:  Liquid  storax,  "  Sweet-gum  "  resin,  or  liquidambar, 
balsam  of  Peru,  and  balsam  of  tolu. 
SECTION  VII.     VOLATILE  OILS. 
Subsection  1.  Camphor  Group. — These  consist  of  solid  oxidized 
hydrocarbons. 
Examples:    Camphor,  borneol,  menthol  crystals. 
Sub-section  2.    lerpene  Group. — It  comprises  liquid  hydrocarbons. 
Examples :  Wood-tar,  tar  and  rosin  oils,  spirits  of  turpentine, 
etc. 
