206 
Uva  ursi! 
/Am.  Jour.  Pharm, 
I     3Iay  1,1871. 
perties  at  all  ;  he  gave  it  in  doses  as  high  as  eight  grains,  and  could 
not  detect  it  in  the  urine. 
When  the  mother -liquor  from  arbutin  is  heated  with  a  dilute  acid' 
(sulphuric  or  muriatic)  a  resinous  body  separates,  which  has  received 
the  name  of  ericolin  ;  this  ngain  is  a  glucoside,  which,  when  treated 
with  a  dilute  acid,  splits  into  grape  sugar,  and  an  odorous  substance 
having  the  character  of  a  volatile  oil,  ericinol ;  both  have  been  noticed 
already  by  Kawalier  in  his  investigation.  In  preparing  ericolin  from 
the  mother  liquor  of  arbutin,  I  found  that  a  portion  of  ericolin  is  de- 
composed as  soon  as  it  forms  into  ericinol,  giving  rise  to  the  strong 
disagreeable  odor  of  the  latter.  Ericolin  is  a  dark  brown  resin,  be- 
coming somewhat  lighter  when  dried  and  rubbed  to  powder  ;  its  chemi- 
cal composition  is  Cgg  H^g  0^^.  Its  decomposition  into  ericinol  is- 
shown  by  the  following : 
Ericolin,  Ericinol.  Grape  Sugar. 
[The  literature  on  ericinol  and  ericolin  is  now  reviewed,  and  their 
occurrence  in  different  plants  spoken  of.  The  precipitate,  obtained 
with  hydrated  oxide  of  lead  was  found  to  contain  tannin,  gallic  and 
malic  acids,  but  to  be  free  from  tartaric  and  citric  acids.  The  pre- 
cipitate obtained  b}^  adding  alcohol  in  a  concentrated  infusion  of  the 
leaves,  contained  gum,  glucose  and  a  lime  salt.  The  leaves,  previously 
exhausted  with  water,  were  treated  with  ether,  and  Trommsdorff"s  urson 
was  prepared  from  the  ethereal  tincture  (see  Am.  Journ.  Ph.,  1854.)] 
Trommsdorft"s  process  directs  the  ethereal  extract  to  be  washed  by 
ether  before  treating  with  alcohol ;  this  removes,  besides  the  coloring 
matter,  some  fatty  matter ;  but  when  operating  upon  larger  quantities, 
I  believe  that  animal  charcoal  will  answer  the  same  purpose.  Another 
way  to  prepare  urson  is  to  percolate  the  leaves,  previously  exhausted 
by  water  with  strong  alcohol  ;  the  dark  green  tincture  deposits  al- 
ready on  standing  a  large  quantity  of  nearly  white  urson,  which  only 
needs  recrystallizing  ;  the  remainder  of  the  tincture  is  evaporated, 
treated  with  water,  and  then  washed  with  ether  and  recrystallized 
from  alcohol.  Urson,  when  pure,  possesses  neither  odor  nor  taste  ; 
it  is  insoluble  in  water,  sparingly  soluble  in  alcohol  and  ether.  It 
is  not  affected. by  alkalies  or  dilute  acids. 
Concentrated  sulphuric  acid  turns  it  black  and  gradually  carbon- 
izes it,  the  acid  assuming  a  red  color.  Concentrated  nitric  acid  turns, 
it  yellow,  gradually  dissolving  it,  giving  off  nitrous  acid.  When  heated,. 
