Am.  Jour.  Pharm. 
June,  1919. 
Pharmacy  of  Tethelin. 
349 
with  suspicion  as  a  substitute  for  Canada  balsam,  especially  since 
the  publication  of  an  article  by  Dowzard7  purporting  to  show  that 
Oregan  balsam  is  a  fictitious  article made  by  dissolving  colophony 
in  turpentine."  He  regards  the  acid  number  of  the  resin  (non- 
volatile residue)  as  indicating  that  Oregon  balsam  contains  colo- 
phony, since  the  two  values  are : 
Oregon  fir  balsam  resin    153 
Colophony    155 
More  recent  work  by  Rabak5  on  commercial  samples  and  of 
Schorger9  on  authentic  samples  of  Oregon  fir  balsam  show  the  acid 
values  of  the  resins  (non- volatile  residues)  to  be  practically  the 
same.  The  former  obtained  an  average  value  of  153  (calculated 
basis  of  70  per  cent,  resin)  and  the  latter  of  166  (calculated).  It 
follows.,  therefore,  that  a  high  acid  value  for  the  resin  does  not  show 
Oregon  fir  balsam  to  be  a  spurious  product  as  assumed  by  Dowzard. 
On  the  other  hand,  it  apparently  does  differentiate  Oregon  fir  balsam 
from  Canada  balsam.  The  constituents  of  these  two  products,  so 
far  as  they  have  been  determined  are,  however,  quite  similar,  and 
it  is  probable  that  in  practice  Oregon  fir  balsam  will,  in  many  cases, 
serve  the  purpose  quite  as  well  as  Canada  balsam  and  at  about  one 
sixth  the  cost. 
United  States  Department  of  Agriculture, 
Forest  Service,  Forest  Products  Laboratory, 
Madison,  Wisconsin. 
(In  Cooperation  with  the  University  of  Wisconsin.) 
THE  PHARMACY  AXD  MANNER  OF  USE  OF  TETHELIX. 
By  George  E.  Ewe. 
Tethelin  is  a  substance  partaking  of  the  nature  of  a  lipoid,  de- 
rived from  the  anterior  lobe  of  the  pituitary  body,  and  was  first 
isolated  by  T.  Brailsford  Robertson,  Ph.D..  D.Sc,  in  1916.  It 
has  been  suggested  by  Robertson1  as  being  the  growth-controlling 
principle  of  the  anterior  lobe  of  the  pituitary  body. 
7  Chemist  and  Druggist  (1904),  page  64;  Allen,  "  Commercial  Organic 
Analysis,"  IV,  79  (note). 
s  Pharmaceutical  Review  (1904),,  22,  293. 
9  Journal  American  Chemical  Society  (1917),  39,  1040. 
1  Robertson,  T.  B..  Jour.  Biolog.  Chem.,  1916,  XXIV,  397,  421. 
