Am.  Jour.  Pharm.") 
Feb.,  1884.  J 
Percentage  of  Alcohol. 
71 
TABLES  OF  PERCENTAGE  AND  SPECIFIC  GRAVITY 
OF  ALCOHOL. 
By  Gustavus  Pile. 
Read  at  the  Pharmaceutical  Meeting,  January  15,  1884. 
In  a  paper  read  at  one  of  the  Phaamaceutical  Meetings  last  spring, 
I  called  attention  to  the  alcohol  tables  of  the  Pharmacopoeia  of  1880, 
and  showed  that  they  differed  materially  from  the  scale  of  Tralles, 
and  might  mislead  one  in  determining  the  value  of  alcoholic  mixtures. 
Alcohol  having  a  specific  gravity  of  *8157  has  been  regarded  as  95 
per  cent,  for  so  long  a  time  that  it  would  seem  to  be  difficult  to  interpret 
it  any  other  way,  but  by  the  adoption  of  the  tables  of  Hehner,  such 
will  be  the  case,  and  95  per  cent,  will  have  a  specific  gravity  of  *8161, 
and  so  on. 
In  order  to  show  some  of  the  differences  between  the  two  tables,  I 
give  a  few  of  the  percentages  from  each,  side  by  side,  the  variations 
between  them  being  seen  at  a  glance. 
Specific  Gravity. 
Tralles 
Hehner. 
Weight. 
Volume. 
Weight. 
Volume. 
1-0000 
•9857 
•00 
8-86 
•oo 
8*05 
10-00 
11-00 
•9751 
16  -29 
20-00 
17*17 
21*09 
•9646 
24-69 
30-00 
25-43 
30  -90 
•9510 
3B-39 
40-00 
34-05 
40-79 
•9335 
42  -52 
50-00 
43-00 
50-57 
•9126 
52  -19 
60-00 
52-41 
60-25 
•8892 
62-50 
70  -00 
62-73 
70-27 
•8631 
73  -59 
80*00 
73-75 
80-19 
•8332 
85-75 
90-00 
85-96 
90-23 
•7939 
100-00 
100-00 
99  -97 
99-98 
As  will  be  here  seen,  the  alcoholometers  as  now  made  will  necessi- 
tate a  correction  each  time  they  are  used ;  and  to  me,  as  a  maker  of 
them,  the  question  will  be  which  table  to  follow  in  the  future.  I 
endeavor  to  have  my  hydrometers  true  to  as  small  a  fraction  as  it  is 
possible  to  read  them,  but  these  tables  show  variations  from  *02  up  to 
nearly  2  whole  degrees,  a  fact  that  cannot  but  lead  to  confusion.  This 
is  unfortunate,  and  is  about  equivalent  to  having  a  new  value  placed 
on  the  present  fluidounce,  and  asking  the  pharmacist  either  to  make 
an  allowance  when  using  his  graduates,  or  else  throw  them  aside  and 
procure  a  new  supply. 
Being  convinced  of  the  unfeasibility  of  displacing  the  scale  of 
