ANoVe0mbe?,hi897m"}      Fermented  and  Distilled  Liquors.  583 
method  is  to  use  a  decinormal  solution  of  sodium  hydrate,  rather 
than  the  official  normal  solution  of  potassium  hydrate,  and  to 
employ  10  c.c.  of  whiskey,  rather  than  100  c.c.  Place  the  sample 
to  be  examined  in  a  flat-bottomed  test  tube,  resting  on  a  piece  of 
white  paper,  add  a  few  drops  of  phenolphthalein  solution — do  not 
use  litmus,  as  it  is  not  sufficiently  delicate — and  run  in  the  soda 
solution  from  a  burette  (graduated  to  a  tenth  c.c).  By  a  little 
practice,  and  especially  by  "  checking"  results,  the  end  reaction  may 
be  very  quickly  and  accurately  determined.  To  measure  the  whis- 
key the  writer  uses  a  5  c.c.  pipette,  graduated  to  the  twentieth  of  a 
c.c.  Probably  one  graduated  to  the  one-tenth  would  answer  equally 
as  well. 
The  results  had,  during  the  past  five  years,  in  determining  the 
total  acidity  of  some  seventy-five  samples  of  whiskey,  according 
to  the  above  method,  in  the  number  of  cubic  centimetres  of  deci- 
normal sodium  hydrate  solution  needed  to  neutralize  10  cubic 
centimetres  of  a  sample,  were  as  follows : 
2893:—!,  i-i,  1-4,  i-8,  1-2,  o*6,  1,  i'i,  i-2,  1-3,  i-8,  1-5,  1-5,  1-5,  1*5,  1-5,  rg, 
1894:— 1-4,  1-2,  16,  i*3,  1-3,  0-9,  0-9,  1 -3,  1 -3,  i-6,  r6,  i-6,  17,  17,  r6. 
1895:- -17,  i-6,  1-4,  1 -3,  1 -3,  1-3,  18,  1-4,  1-5,  r6,  1-9,  r6,  rS,  17,  1-4,  1*4. 
1896:— 1-2,  V2,  it,  1-3,  17,  17,  1*2,  i -5,  1-5,  1-5,  1*5,  1-4. 
1897:— 1-6,  1-3,  x'3,  17,  1-3,  1-2,  1-3,  1-5,  1-3,  0-4,  0-5,  o-6,  i'6,  17. 
It  is  important  to  note  that  the  acidity  of  whiskey  does  not 
increase  with  age  beyond  a  certain  point.  In  May,  1895, the  writer 
examined  ten  samples  of  whiskey.  None  of  the  samples  were  less 
than  three  years  old.  The  results  were  in  cubic  centimetres  of 
decinormal  sodium  hydrate  solution  used  to  neutralize  10  c.c.  of 
whiskey,  as  follows : 
17,  i-6,  1-4,  1*3,  1*3,  i-8  1-4,  1-5,  i*6,  r6. 
The  same  samples  were  examined  a  few  days  since  (October,  1897), 
and  the  acidity  was  found  to  be  unchanged. 
If  valerianic  acid  is  the  main  acid  in  whiskey,  the  reaction  in  neu- 
tralization with  sodium  hydrate  would  be  as  follows: 
HC5H902  +  NaHO  =  NaC5H9Oa  +  H20 
10177         39-96         12377  1796 
Assuming  that,  in  good  whiskey,  an  average  of  75  c.c.  of  deci- 
