582  Fermented  and  Distilled  Liquors.    { ^oVembe^T 
Let  us  first  note  the  inaccuracies  of  these  statements.  While 
fusel  oil  or  amylic  alcohol  is  found  in  recently  distilled  whiskeys,  it 
is  not  found  in  those  that  have  been  properly  aged,  or,  if  present, 
it  is  present,  as  stated  by  the  Pharmacopoeia,  in  traces  only.  The 
Pharmacopoeia  requires  the  absence  of  all  fusel  oil  from  the  official 
brandy.  As  to  the  oak  tannin  in  whiskey  and  brandy,  from  the 
casks,  it  is  only  present  in  traces,  and  it  is  difficult  to  see  how  it  can 
be  regarded  as  a  very  undesirable  impurity. 
If  "  liquors "  have  therapeutic  worth  over  simple  mixtures  of 
alcohol  and  water  in  fixed  strengths — and  the  burden  of  clinical 
evidence  is  that  they  have — this  value  must  be  due  to  the  extractive 
matters  contained  in  them ;  and  it  is  upon  this  line,  with  regard  to 
a  certain  constituent  of  whiskey,  that  a  few  words  may  be  said. 
During  the  past  five  years  the  writer  has  examined  many  samples 
of  whiskey  chemically,  and  next  to  the  alcoholic  strength  and  the 
absence  of  fusel  oil,  one  of  the  most  important  factors  in  such 
examinations  has  been  the  determination  of  the  total  acidity.  The 
importance  of  this  factor  has  been  generally  overlooked,  and  was 
pointed  out  to  me  by  the  late  Prof.  John  M.  Maisch,  who  said  that 
he  had  examined  many  barrels  of  whiskey  during  the  Civil  War, 
lor  the  Government,  and  always  found  that  the  best  whiskeys  had 
the  highest  acidity.  He  referred  me  to  a  paper  in  the  American 
Journal  of  Pharmacy  (1859,  p.  573),  which  he  had  translated  from 
the  German,  wherein  S.  J.  Kappel  showed  the  presence  of  valerianic 
acid,  and  the  absence  of  acetic  acid,  in  potato  and  in  rye  whiskeys, 
and  expressed  the  opinion  that  while  valerianic  acid  was  probably 
the  main  acid  of  whiskeys,  this  had  not  been  positively  deter- 
mined. Since  then,  the  writer  has  been  especially  observant  of  the 
acid  factor  in  whiskey  examinations,  and  has  found  that,  generally, 
the  oldest,  fusel-oil-free,  highest-priced,  and  most  strongly  alcoholic 
whiskey  has  the  highest  acidity.  Occasionally  there  is  an  exception. 
A  raw  whiskey  may  be  so  refined  before  aging  that  it  will 
not  have  the  usual  amount  of  the  acid-forming  compounds,  and 
hence  show  a  low  acidity. 
The  Pharmacopoeia  of  1890  demands  a  whiskey  "at  least  two 
years  old,"  and  requires  that  to  render  100  c.c.  of  whiskey  dis- 
tinctly alkaline  to  litmus  there  should  be  required  not  more  than 
1-2  c.c.  of  normal  potassium  hydrate  solution. 
To  determine  the  acidity,  a  very  much  better  way  than  the  official 
