Am.  Jour.  Pharm.  1 
Dec,  1883.  / 
Oleum  Rusci. 
627 
OLEUM  RUSCI.i 
B  Y    P  E  T  E  R    M  A  C  E  W  A  N. 
During  the  past  two  or  three  years  a  demand  has  sprung  up  for 
oleum  rusci,  and  considerable  doubt  has  been  expressed  as  to  its  nature 
and  quality,  articles  of  different  characters  having  been  supplied. 
It  would  appear  from  the  name  that  the  article  has  some  relation  to 
butcher's  broom  (Ruscus  aculeatus),  but  we  learn  from  various  sources 
that  it  is  merely  one  of  the  synonyms  of  the  empyreumatic  oil  of  com- 
mon birch  (Betula  alba).  Thus  tlie  Danish  Pharmacopoeia,  1805,  has 
the  oil  under  these  names,  "  Oleum  betulinum,  oleum  rusci,  oleum 
brusci/'  the  latter  being  another  name  for  the  butcher's  broom.  These 
names  are  quoted  in  the  Norwegian  Pharmacopoeia  of  1854  under 
^'  Pix  epidermidis  betulse  alb?e ; "  more  recently  we  find  that  Hager 
uses  the  synonym  for  the  birch  tar  oil,  and  the  Dutch  Society  for  the 
Advancement  of  Pharmacy  have  it  as  Oleum  betulse  rectificatum, 
oleum  rusci."  ^ 
T  can  find  no  explanation  of  the  association  of  the  words  "Ruscus" 
and  "  Bruscus "  with  this  birch  product,  and  can  offer  none,  unless 
^^Brzoza"  (Polish for  birch)  may  have  been  corrupted  into  "Bruscus" 
and  thence  into  "  Ruscus."  At  all  events  it  is  beyond  dispute  that 
oleum  rusci  is  birch  tar  oil. 
The  oil  has  been  long  known  as  that  used  in  currying  Russia  leather, 
to  which  it  imparts  the  peculiar  odor  and  lasting  properties  that  are 
€0  much  admired  ;  it  is  chiefly  made  in  Russia  and  Poland.  The  bark, 
and  sometimes  the  rootlets  and  twigs,  are  subjected  to  dry  distillation, 
the  retort  being  of  clay  and  connected  by  wooden  pipes  to  a  receiver 
placed  in  the  earth.  Hager  states  that  this  oil  is  a  thickish  liquid  of 
a  reddish-brown  or  brown-black  color,  peculiar  empyreumatic  odor, 
and  sparingly  soluble  in  water,  but  soluble  in  alcohol  and  ether  to  a 
^reat  extent.  The  re-distilled  oil  of  the  Dutch  Society  is  said  to  be  a 
red-brown  volatile  oil,  sp.  gr.  0'800-0*987,  soluble  in  an  equal  weight 
of  alcohol  and  imparting  an  acid  reaction  to  water.  Birch  bark  has  a 
mildly  fragrant  odor,  and  by  gentle  heating  yields  a  sublimate  of  birch 
camphor  or  betulin  (C3gHgo03).  This  body,  as  obtained  from  the  bark 
by  exhaustion  with  alcohol,  is  odorless  and  tasteless,  but  when  sub- 
jected to  a  high  temperature  (about  258°C.)  it  gives  off  vapors  smelling 
1  The  greater  portion  of  this  paper  was  read  before  the  Edinburgh  Chem- 
ists' Assistants  and  Apprentices'  Association,  November  7,  1883. 
Pharrn.  Journ.  [3],  xiii,  10. 
