Am.  Jour.  Pharm. » 
March,  1889.  J 
The  Metameric  Amyl  Nitrites. 
151 
luted  with  water,  neutralized  with  barium  carbonate,  and  filtered.  The 
solution  was  concentrated  and  fractionally  crystallized,  the  fractions, 
which  were  early  obtained,  were  isolated  and  separately  recrystallized 
about  twenty-three  times.  From  some  of  the  salt  thus  purified  the 
alcohol  was  regenerated,  dried  and  distilled.  It  boiled  at  129°-130° 
C,  and  at  15°  C.  its  specific  gravity  was  *813.  The  liquid  was  found 
still  to  possess  rotatory  power.  At  15°  C.  in  a  tube  200  mm.  long 
the  rotation  was  observed  to  be  -0*45°,  so  that  the  repeated  recrystal- 
lization  of  the  barium  salts  had  only  removed  two-thirds  of  the  active 
alcohol  which  the  liquid  originally  contained.  The  regenerated  liquid 
still  contained  5*1  per  cent,  of  the  active  alcohol.  Since  a  comparison 
of  the  physiological  effects  of  several  specimens  of  a-amyl  nitrite,  as- 
sociated with  different  amounts  of  /3-amyl  nitrite,  with  the  physiologi- 
cal effect  of  pure  a-amyl  nitrite,  would  enable  the  action  of  3-amyl 
nitrite  to  be  inferred,  the  above-mentioned  alcohols  were  converted 
into  the  nitrites,  and  their  action  is  being  physiologically  examined  by 
Professor  Cash.  The  nitrites  boiled  at  96°-97°,  and  the  specific 
gravity  of  the  liquid  was  0*874  at  15°  (water  at  15°=1). 
The  remainder  of  the  barium  salts  was  now  dissolved  in  a  large 
quantity  of  water,  and  the  dilute  solution  allowed  to  crystallize  slowly. 
The  salt  obtained  was  separated  from  the  mother-liquid  and  again 
recrystallized  twelve  times.  The  barium  salt  had  now  been  recrystal- 
lized thirty-five  times.  On  regenerating  the  alcohol  and  drying  it,  the 
boiling  point  was  found  to  be  131°  C.  (bar.  759  mm.),  the  whole  of 
the  thermometric  column  being  immersed  in  the  vapor.  The  specific 
gravity  of  the  liquid  at  15°  C.  was  0*8140  (water  at  15c=d).  The 
alcohol  was  now  practically  inactive,  the  rotation  effected  in  a  column 
200  mm.  long  being  only  one-tenth  of  a  degree.1  The  nitrite  was 
now  prepared  from  this  alcohol  by  the  method  which  has  been  previ- 
ously described,  and  its  characters  have  been  carefully  examined.  It 
was  shown  to  be  pure  by  the  method  which  has  already  been  alluded 
to.  (Weight  of  liquid  taken  0*1787  gram;  pure  amyl  nitrite  found 
0*1797  gram.).  The  boiling  point  determined  with  a  standard  ther- 
mometer is  97°  C.  (bar.  758*5  mm).  Its  specific  gravity  at  15°  is  0*880 
(water  at  15°=1).  The  liquid  was  virtually  inactive,  showing  a  dex- 
trorotation in  a  tube  200  mm.  long  of  only  one-twentieth  of  a  degree. 
1  A  specimen  prepared  by  Pedler  and  recently  examined  by  Dr.  Perkin 
(Journ.  Chem.  Soc,  1884,  470),  exhibited  a  rotation  of  -0*9°  in  a  column  200  mm. 
long.   The  specific  gravity  at  15°  was  0*8135,  and  the  boiling  point  131*5°  C. 
