Nitrite  of  A  my  I. 
A.m.  Jotir.  Pharm. 
Oct.,  1878. 
should  be  of  constant  strength.  With  the  view  of  ascertaining  whether 
either  of  these  conditions  holds  good  with  the  article  in  the  market,  I 
procured  several  samples  from  such  sources  that  they  may  be  regarded 
as  fairly  representative  and  submitted  them  to  examination  along  with 
a  quantity  (a)  prepared  by  ourselves.  As  there  is  considerable  diverg- 
ence in  the  boiling  point  of  amylic  nitrite  as  given  by  different  authori- 
ties, the  fraction  90°-ioo°C.  was  collected  as  correct.  This  portion 
had  invariably  the  proper  spec.  grav.  of  "877.  The  results  of  the 
examination  are  embodied  in  the  table  annexed. 
Sample 
A 
B 
C 
D 
E 
F 
Specific  Gravity, 
•877 
'876 
•864 
•875 
•875 
•875 
Below  900,    .  . 
.  5-0 
3"o 
34-6 
a-6 
o'o 
52*0 
90°-iooc>, 
.  85-0 
65*0 
6-7 
47'5 
11-5 
33*3 
Above  ioo°, 
8-o 
28-0. 
51-7 
45  7 
83-9 
11  4 
Water,     .    .  . 
o'o 
00 
i-8 
00 
2'2 
O'O 
2'0 
4*o 
5'* 
42 
2 -4 
3*3 
IOO'O 
IOO'O 
ICO'O 
100  0 
IOO'O 
IOO'O 
These  figures  give  the  results  of  a  single  rectification.  Of  course, 
on  again  rectifying  the  lower  and  higher  fractions  an  additional  quan- 
tity of  nitrite  of  amyl  would  be  obtained  ;  but  the  numbers  are  suffi- 
cient for  the  purpose  of  comparison.  The  samples  C  and  E  are  of  very 
poor  quality,  E  being  probably  the  inferior,  because,  although  it  appar- 
ently contains  a  larger  percentage  of  amylic  nitrite  than  C,  it  yields  a 
large  proportion  boiling  above  100°,  the  temperature  rising  to  2300 
before  the  distillation  was  stopped,  leaving  a  black  oily  residue  in  the 
flask.  The  odor  of  this  sample  was  quite  different  from  that  of  gen- 
uine nitrite  of  amyl.  It  will  thus  be  seen  that  out  of  five  specimens 
examined,  two  were  of  very  inferior  quality.  That  it  is  difficult  com- 
pletely to  separate  the  nitrite  of  amyl  by  rectification  from  the  accom- 
panying substances  is  shown  by  the  numbers  here  given.  The  frac- 
tions boiling  below  900  and  above  ioo°  from  the  sample  F  were  recti- 
fied together  in  the  same  way  as  before,  the  process  being  repeated 
twice. 
I.  59  0  cc.  gave  13*0  cc.  =  22*0  per  cent.  900 — 1000 
II.  43-0  8-o       =  l8'6 
III.  33-5  5-0       =  14-9 
In  passing  judgment,  however,  on  such  a  substance  as  nitrite  of  amyl, 
the  question  meets  us  at  the  very  outset,  What  degree  of  purity  have  we 
a  right  to  expect  in  this  body  ?    In  the  case  of  amylic  nitrite  the  ques- 
