734 
Purified  Ether. 
/Am.  Jour.  Pharm. 
November,  19 19. 
anesthetic  in  the  full  sense  of  the  term ;  that  it  is  narcotic,  but  not 
analgesic,  and  that  it  is  to  traces  of  certain  "  impurities  "  formed  in 
the  manufacture  of  the  ether  to  which  the  proper  anesthetic  effects 
are  due ;  suggesting  ethylene  as  being  the  analgesic  substance.  In 
furtherance  of  this  view,  some  remarkable  demonstrations  were 
given  of  the  combined  effect  'of  ether  and  ethylene,  but  beyond  mere 
mention  of  this  I  must  refer  those  interested  in  the  matter  to  the 
original  communication.2  The  point  that  it  is  desired  to  emphasize 
in  these  notes  is :  Is  there  any  real  difference  between  the  action  of 
these  low  boiling  mixed  ethers  and  the  higher  boiling  official  article, 
and  is  there  any  valid  reason  for  the  preferment  of  the  one  to  the 
exclusion  of  the  other  from  the  Pharmacopoeia?  The  difficulty  is 
that  one  cannot  but  suppose  there  were  definite  reasons  for  making 
the  restrictions  of  the  Pharmacopoeia,  yet  there  remains  the  indis- 
putable fact  that  very  large  quantities  of  unofficial  "  anesthetic 
ether"  are  requisitioned  (even,  perhaps,  larger  quantities  of  this 
than  of  the  literally  official  article)  and  apparently  used  with  suc- 
cess. If  there  is  no  practical  difference,  then  it  is  very  desirable  that 
the  official  requirements  should  be  modified  so  as  to  include  both 
types ;  but  if  an  undoubted  difference  is  observable,  then  it  is  still 
more  desirable  that  the  two  types  should  have  recognition,  so  that 
all  ambiguity  might  be  removed  and  a  distinction  drawn  as  to  the 
special  adaptations  of  the  particular  ether.  This  question  is  one  the 
solution  of  which  is  medical  rather  than  pharmaceutical,  for  it  is  to 
do  with  observed  physiological  effect;  but  it  is  certainly  very  de- 
sirable for  the  pharmacist  to  know  exactly  where  he  stands  when 
he  is  called  upon  to  handle  material  ostensibly  the  same,  but  vir- 
tually different,  which  is  used  without  recognition  of  probable  dif- 
ferences in  properties. 
Closely  connected  with  this  is  the  demand  for  "  absence  of  methyl 
compounds  "  from  purified  ether.  One  might,  perhaps,  be  allowed 
to  express  the  opinion  here  that  it  would  be  a  great  advantage  in 
cases  of  this  sort  where  mere  traces  are  being  dealt  with,  if  some- 
thing rather  more  specific  than  bare  absence  of  a  class  of  compounds 
was  required.  This  is  all  very  well  where  the  desire  is  simply  to 
maintain  a  standard  of  commercial  purity,  but  it  is  an  entirely  dif- 
ferent thing  when  tests  are  introduced  having  behind  them  the  idea 
of  physiological  effect.  Such  tests  should  be  very  distinctly  noted 
and  treated  in  as  fully  an  explanatory  a  manner  as  possible.  For 
2Journ.  Canad.  Med.  Soc,  Sept.,  1917;  Med.  Rec,  Mar.  16,  1918. 
