STRENGTH  OF  COMMERCIAL  ALCOHOL. 
391 
I  am  not  aware  that;  Soubeiran's  idea  of  obtaining  ether  at  one 
operation  has  ever  been  successfully  applied,  if  it  has,  the  meth- 
ods and  results  have  not  been  published. 
U.  S.  Naval  Laboratory,  New  York,  July  1856. 
NOTE  ON  THE  STRENGTH  OF  COMMERCIAL  ALCOHOL. 
By  John  Buck. 
Prof.  Procter: 
Dear  Sir, —  I  have  read  in  the  journal  the  article  of  Mr. 
Mead,  also  the  replies  of  Mr.  Sharp  and  Mr.  Pile,  and  it  does 
not  seem  to  me  that  either  of  them  explain  the  dilemma  in  which 
Mr.  Mead  seems  to  be  with  regard  to  his  alcohol.  Mr.  Sharp 
says  nothing  about  it,  merely  answering  his  question  on  the 
Government  standard  of  the  different  proofs,  and  Mr.  Pile  con- 
gratulates Mr.  Mead  on  his  getting  a  better  article  than  he  con- 
tracted for,  an  accident  which  he  is  confident  does  not  occur 
elsewhere.  Now  I  do  not  think  it  is  a  matter  of  accident,  nor 
that  he  got  a  better  article  than  he  contracted  for,  but  whether 
it  is  peculiar  to  this  vicinity  I  cannot  say.  I  do  not  consider 
myself  capable  of  giving  a  scientific  explanation  of  the  subject, 
but  having  got  into  the  same  dilemma,  and  having  arrived  at  the 
same  results  of  which  he  speaks,  I  was  led  to  look  into  the 
subject,  and  will  state  to  you  how  I  explained  the  matter  to  my 
own  satisfaction. 
I  had  tested  several  barrels  of  alcohol  which  I  purchased  at 
different  times,  which  were  marked  80  per  cent,  and  had  found 
them  to  be  90  per  cent,  by  volume ;  I  concluded  there  could  be 
no  mistake,  but  that  80  per  cent,  with  them  must  be  different 
from  what  I  understood  as  80  per  cent. 
I  took  some  pains  to  enquire  of  different  distillers,  what  per 
cent,  by  volume  they  represented  by  their  80  per  cent,  alcohol, 
and  I  found  they  did  not  seem  to  understand  much  about  the 
use  of  any  other  instrument  except  the  one  used  by  themselves, 
(it  is  not  the  same  as  those  used  by  Government.)  The  only  in- 
formation I  could  get  was,  that  when  they  say  a  spirit  is  80  per 
cent,  they  mean  that  100  gallons  of  that  spirit  will  require  80 
gallons  of  water  to  reduce  it  to  proof  spirit;  that  is,  100  gallons 
of  80  per  cent,  alcohol  is  equal  to  180  gallons  proof  spirit,  (100 
