242 
AMYLENE. 
agents  which  I  have  exhibited  as  anaesthetics  to  the  human  sub- 
ject, in  addition  to  ether  and  chloroform,  have  as  yet  been  but 
few.  They  are  nitric  ether,  Dutch  liquid,  benzin  or  benzole,  a 
bichloride  of  carbon,  made  by  decomposing  chloroform  with 
chlorine  gas,  the  monochlorinetted  chloride  of  ethyle,  and 
amylene,  the  subject  of  this  paper.  Nitric  ether  was  exhibited 
also  by  Dr.  Simpson,  and  Dutch  liquid  by  him  and  Dr.  Nunneley. 
These  substances  possess  no  advantage  over  chloroform,  unless 
it  be  in  their  slower  action,  while  in  other  respects  they  are 
scarcely  so  agreeable.  With  regard  to  benzin,  I  discontinued 
the  use  of  it  on  account  of  convulsive  tremors  which  it  occasioned 
in  a  case  of  amputation  in  St.  George's  Hospital.  I  found  that 
these  tremors  are  a  constant  result  when  its  effects  reach  a  cer- 
tain stage.  I  administered  the  chlorinetted  muriatic  ether  in 
twenty  surgical  operations  in  the  summer  of  1851,  chiefly  in 
King's  College  Hospital.  Its  sensible  and  physical  properties 
and  its  effects,  are  nearly  the  same  as  those  of  chloroform,  but  I 
thought  that  it  might  possess  some  advantage  in  the  circumstance 
that,  being  less  volatile,  while  its  other  properties  are  the  same, 
it  would  be  less  liable  to  cause  accident,  even  if  incautiously 
used.  I  was,  however,  prevented  from  using  it  further,  owing 
to  the  great  difficulty  of  procuring  it  in  a  state  of  purity."  He 
further  states :  "  I  was  not  aware  of  the  existence  of  amylene 
till  a  few  months  ago,  or  I  should  have  tried  it  sooner ;  for  I 
made  inquiry  in  1848  for  a  substance  named  eupion,  by  Reichen- 
bach,  its  discoverer,  but  was  unable  to  obtain  it.  Eupion  is  a 
carbo-hydrogen,  described  as  having  all  the  physical  characters 
which  belong  to  amylene,  though  obtained  in  a  different  way, 
and  I  believe  it  is  the  same  substance.  Reichenbach  obtained  it 
from  coal-tar,  but  other  chemists  have  not  been  able  to  make  it." 
Dr.  Snow  describes  several  cases  in  which  he  has  administered 
amylene,  and  says  : 
"  The  relative  advantages  and  disadvantages  of  amylene  may, 
as  nearly  as  I  can  judge,  be  summed  up  as  follows  : — In  regard 
to  its  odor,  it  is  more  objectionable  than  chloroform,  but  much 
less  so  than  sulphuric  ether.  The  odor  of  any  volatile  substance 
is,  however,  no  longer  perceived  after  a  patient  begins  to  inhale. 
In  respect  to  its  pungency,  it  has  a  great  advantage  over  both 
ether  and  chloroform,  being  much  less  pungent  than  either  of 
