CHEMICAL   RESEARCHES   ON  AMYLENE. 
415 
but  this  experiment  shows,  that  the  dry  chloride  of  zinc  has  the 
property  of  removing  this  alcohol,  without  affecting  the  amylene. 
These  experiments  go  to  show  the  difficulty,  not  to  say  im- 
possibility of  discovering  a  facile  and  inexpensive  method  of  ob- 
taining pure  amylene.  Let  us  examine  the  qualities  of  the  amy- 
lenes in  use :  I  have  taken  four  different  preparations,  namely  ; 
1,  that  of  Dr.  Snow  (A) ;  2,  that  of  M.  Menier  (B) ;  3,  that 
which  I  have  prepared  according  to  the  process  of  M.  Hepp  (C)  ; 
4,  the  amylene  obtained  in  the  sixth  experiment  (D).  The  fixity 
of  the  boiling  points,  being  one  of  the  principal  means  of  defin- 
ing a  liquor  compound,  I  distilled  in  succession  these  four  amy- 
lenes in  a  small  retort  provided  with  a  thermometer.  The 
following  was  the  result : 
Boiling  of  product  A  began  at  +  86°  F.  and  closed  at  +140°  F. 
a  B     "      +  84°  "  «        4-167°  " 
a  C     "       +  86°  "  "        +143-6° " 
"  D     "       +  88°  "  "        +134°  " 
This  variation  in  the  degrees  necessary  to  the  ebullition  of 
these  products,  indicates  not  only  the  presence  of  carburets  more 
volatile  than  amylene ;  but,  on  the  contrary,  also  the  presence 
of  bodies  less  volatile. 
Action  of  Potassium  on  impure  Amylene.-— The  amylene 
having  a  badly  defined  character  may  be  nothing  other  than  a 
mixture  of  the  different  carburets,  and  of  amylene  properly  so 
called.  In  such  case  potassium  would  have  no  more  action  on 
them  than  it  would  have  on  the  oil  of  naptha,  in  which  it  is  placed 
for  preservation.  But  such  is  not  found  to  be  their  condition, 
the  potassium  oxydating  in  these  amylenes,  and  giving  out  hydro- 
gen gas  in  abundance.  In  order  to  determine  the  quantity  given 
out,  I  have  taken  a  little  dry  flask  to  which  I  adjusted  a  curved 
tube,  passing  it  into  a  hydro-pneumatic  receiver  with  a  gradu- 
ated scale,  and  I  have  placed  successively  in  this  flask  an  equal 
weight  of  the  aforesaid  amylenes,  with  a  large  excess  of  brilliant 
potassium  cut  into  small  pieces.  The  disengagement  of  gas  was 
rapid  in  each  experiment : 
3  grm.  of  amylene  A,  in  contact  with  potassium,  gave  out  64  cubic  centimetres  of  hvdro.  gas. 
3grm.         "       B,  "  "  91  «  "  « 
3  grm,         "       C,  "  "  75  "  « 
3  grm.         ,?       D,  "  "  69  «  " 
The  action  of  Potash  on  impure  Amylene. — The  oxydation  of 
potassium,  and  the  consequent  disengagement  of  hydrogen,  would 
