86 
Oleum  Betulce  Lentce. 
Am.  Jour.  Pharm. 
Feb.,  1884. 
contain  a  hydrocarbon,  and  it  was  owing  to  this  strong  evidence  that, 
at  the  Washington  meeting,  I  unhesitatingly  said  that  there  was  no 
reason  why  the  oil  should  not  contain  the  terpene.  I  believe,  under 
the  circumstances,  I  was  justified  in  so  speaking.  The  interesting  dis- 
cussion which  followed  the  reading  of  my  paper  threw  out  suggestions 
which  caused  me  to  make  further  investigations. 
— 
It  was  my  intention  to  spend  several  days  in  the  birch  woods,  as  I 
had  invitations  extended  to  do  so,  and  witness  the  process  of  distilla- 
tion more  critically  than  I  did  on  former  occasions,  but  I  was  unable 
to  fix  a  time  to  suit  the  convenience  of  all  parties  interested,  owing  to 
the  small  amount  of  oil  made.  During  the  past  few  months  the  stills 
were  not  in  operation,  the  price  of  the  oil  being  too  low  to  compensate 
the  distillers  for  their  labor.  However,  my  friend  Mr.  C.  M.  Briggsr 
a  pharmacist  of  Carbon  county,  to  whom  I  am  much  indebted  for 
many  favors,  spent  a  day  at  one  of  the  best  stills  in  the  region,  which 
is  worked  by  a  man  who  thoroughly  understands  his  business,  and  he 
obtained  for  me  the  product  of  the  distillation  of  600  pounds  of  mate- 
rial, which  I  here  exhibit.  The  large  jar  (Mason's  fruit  jar)  contains 
the  oil  just  as  it  was  made,  with  some  water  and  dirt.  Owing  to  an 
accident,  about  six  ounces  of  the  oil  were  lost.  The  yield  was  about 
one  pound,  or  one-sixth  of  one  per  cent.,  which  was  small.  The 
amount  of  "  milk  "  (or  water  impregnated  with  oil),  condensed  in  the 
exhaustion  of  the  bark,  amounts  to  30  gallons.  The  jar  was  used  as 
the  receptacle  for  the  oil,  and  was  placed  in  a  pail ;  as  the  pail  fills 
with  the  "  milk  "  it  is  emptied  into  a  barrel,  and  put  away  to  be  used 
for  another  "  run/'  as  it  is  called,  meaning  the  next  distillation.  The 
bottle  labeled  milk  is  a  sample  of  the  product  nearing  the  close  of  the 
distillation.  When  received  it  was  quite  milky,  but  now  the  oil  has 
separated,  and  of  course  the  milkiness  has  disappeared,  but  by  agita- 
tion it  can  be  restored ;  the  oily  globules  of  a  dirty  color  can  be  seen 
at  the  bottom  of  the. vial.  The  "milk"  contains  about  2  ounces  of 
the  oil  in  every  25  gallons.  The  pieces  of  birch  exhibited  have  had 
the  oil  taken  out,  and  will  give  an  idea  as  to  the  size  of  the  pieces 
used  in  the  extraction  of  the  oil. 
There  was  also  another  bottle  received  by  the  writer,  marked 
"  unknown,"  and  said  to  contain  "  light  oil,"  or  "  light  ring,"  exclu- 
sively, and  which,  from  previous  information  received,  was  considered 
to  be  a  hydrocarbon.  The  vial  contained  4J  fluidounces,  which  was 
reported  to  me  as  having  been  skimmed  from  five  pounds  of  oil  before 
