AMYLENE. 
243 
them.  Thus,  whilst  the  patient,  especially  if  a  female,  often 
complains  of  a  choking  feeling  and  want  of  breath,  in  commenc- 
ing to  inhale  chloroform,  and  two  or  three  minutes  are  lost  before 
the  vapor  can  be  inhaled  in  any  useful  quantity,  she  can  begin 
to  inhale  the  amylene  of  full  strength  within  half  a  minute  from 
commencing,  and  the  operation  may  generally  be  begun  within 
three  minutes.  In  the  amount  which  suffices  to  produce  insensi- 
bility, it  is  intermediate  between  chloroform  and  ether,  chloro- 
form having  the  advantage.  Amylene  has  an  advantage,  in  pre- 
venting pain  with  a  less  profound  stupor  than  that  occasioned 
by  the  other  agents,  and  in  the  ready  waking  and  recovery  of 
the  patient  it  has  an  advantage  over  chloroform,  and  a  still 
greater  advantage  over  ether.  Its  probable  safety  I  have  spoken 
of;*  and  the  greatest  advantage  of  all,  if  it  should  continue  to  be 
met  with  in  all  cases,  is  the  absence  of  sickness  from  its  use.  The 
almost  entire  absence  of  struggling  and  rigidity  may  also  be 
mentioned  as  an  advantage  of  amylene  over  ether  and  chloro- 
form." 
Preparation  and  Properties  of  amylene  Amylene  was  dis- 
covered and  described  in  1844  by  M.  Balard,  of  Paris.  It  is 
made  by  distilling  fusel  oil,  or  amylic  alcohol  (the  only  liquid 
which  is  separated  from  spirit  of  wine  in  the  process  of  rectifica- 
tion,) with  chloride  of  zinc.  On  adding  the  fusel  oil  to  a  con- 
centrated solution  of  chloride  of  zine  while  they  are  cold,  solution 
or  admixture  does  not  take  place,  but  on  applying  heat  they  mix 
and  form  a  homogeneous  liquid,  which  begins  to  distil  at  a  tem- 
perature of  about  266°  Fah.  On  re-distilling  the  product  thus 
obtained,  the  ebullition  which  commences  at  140°  Fah.,  rises 
during  the  process  to  about  570°  Fah.  The  most  volatile  parts 
of  this  distillation  are  to  be  separated,  and  agitated  with  concen- 
trated sulphuric  acid,  when  the  amylene  in  a  pure  state  will  rise 
to  the  surface.  It  is  colorless,  very  mobile,  and  has  a  low  specific 
gravity  (stated  by  Dr.  Snow  to  be  0*659  at  56°  Fah.)  Its  boil- 
ing point  is  102°  Fah.,  and  the  density  of  its  vapor  is  2-45.  It 
'  has  a  peculiar  and  disagreeable  smell.  Its  composition  is  repre- 
sented by  the  formula  C10  Hl0.    It  is  soluble  in  alcohol  and  ether 
*  The  author  states,  «  While  I  cannot  venture  to  predict  for  it  the  abso- 
lute safety  which  seems  to  attend  sulphuric  ether  under  all  circumstances, 
I  confidently  trust  that  it  will  be  perfectly  safe  with  careful  management." 
