ii4 
Alcoholmetrical  Table. 
Am.  Jour.  Pharm. 
Mar.,  1879. 
various  proportions  of  water  as  might  be  used  by  the  pharmacist  in  the 
preparation  of  menstruums. 
The  table  here  given  is  not  presented  as  entirely  correct  ;  but  it  is 
believed  that  the  figures  are  sufficiently  accurate  for  use  in  practical 
pharmacy,  for  which  purpose  alone  the  table  was  prepared. 
As  it  is  proposed  to  use  only  parts  by  weight  in  the  next  United 
States  Pharmacopoeia,  the  quantities  of  alcohol  and  water  were  in  each 
case  so  taken. 
The  first  five  lines  in  the  table  give  the  strength  of  different  spirits 
as  found  in  the  market.  The  extra  Cologne  spirit  differs  from  the 
Cologne  spirit  by  being  a  portion  reserved  from  the  first  part  of  the 
distillation  ;  the  Cologne  spirit  is  the  entire  product  of  deodorized 
alcohol  obtained  in  the  run  ;  the  95  per  cent,  alcohol  is  that  in  most 
general  use,  and  it  is  often  as  free  from  odor  as  the  Cologne  spirit ; 
neutral  sweet  spirit  is  very  extensively  used,  under  various  names,  in 
the  liquor  trade,  and  might  be  employed  with  advantage  in  pharmacy. 
The  percentages  by  volume  given  in  the  table  are  too  high  in  the  ten 
lower  items,  but  this  error  in  most  of  them  does  not  exceed  one-fourth 
of  one  per  cent.,  and  in  some  is  much  less. 
The  percentage  by  volume  was  obtained  by  Tralles'  centesimal 
hydrometer,  and  the  book  of  tables  prepared  by  Prof.  McCulloh  for  the 
use  of  the  revenue  officers  of  the  United  States.  The  percentages  by 
weight  were  obtained  by  the  following  rule,  taken  from  Muspratt's 
"  Chemistry,"  page  118  :  "  The  content,  by  weight,of  alcohol  in  a 
liquid,  the  centesimal  value  of  which  per  volume  has  been  found,  is 
ascertained  by  a  simple  calculation.  This  operation  is  done  by  multi- 
plying the  content  per  volume  of  alcohol  into  the  specific  gravity  of 
absolute  alcohol,  and  dividing  the  product  by  the  specific  gravity  of  the 
liquid  and  page  131  :  "Knowing  the  percentage  volume  of  alcohol 
in  a  liquid  at  any  temperature,  the  same  results  are  arrived  at  when 
such  percentage  is  multiplied  by  the  specific  gravity  of  the  pure  anhy- 
drous spirit  at  the  normal  thermometric  degree — 07939  in  Tralles' 
tables,  and  07947  in  Gay-Lussac's — and  dividing  this  product  by  the 
density  of  the  liquid  at  the  observed  temperature."  But  07938  being 
now  more  generally  considered  as  the  specific  gravity  of  anhydrous 
alcohol,  that  was  taken  as  the  basis  of  the  calculations  to  obtain  the 
percentage  by  weight.  The  percentage  by  weight  was  then  compared 
with  the  specific  gravity  in  Fownes'  table,  to  correct  error  due  to  differ- 
