Am^our^pharm.  j    Fluid  Extracts  of  the  New  Pharmacopoeia,  241 
All  of  the  formulas  for  fluid  extracts  requiring  the  use  of  alcohol, 
it  seemed  advisable  to  examine  commercial  specimens  as  to  the  actual 
percentage  of  absolute  alcohol  contained  therein.  Five  samples,  from 
as  many  different  manufacturers,  were  therefore  obtained  and  examined, 
with  the  following  results,  at  15-6°  C.  (60°  F.) 
No. 
Specific  gravity. 
Percentage  of  absolute  alcohol. 
By  weight. 
By  volume. 
1 
•8185 
91^54 
94-38 
2 
•8190 
91  ^36 
94-26 
3 
•8196 
91^14 
94-10 
4 
•8207 
90-75 
93-82 
5 
•8265 
88-56 
92-21 
The  officinal  alcohol  (s.g.  '820),  containing  ninety-one  per  cent,  by 
weight  and  ninety-four  per  cent,  by  volume,  it  will  be  observed  that 
three  of  the  five  specimens  contain  a  slightly  larger  percentage  of  abso- 
lute alcohol  than  the  officinal ;  and  also  that  only  one  of  the  samples 
is  considerably  below  the  officinal  standard,  and  this  one  is  said  to  be 
not  the  product  of  a  regular  manufacturer  of  alcohol,  but  the  surplus, 
or  rejected  goods,  which  have  been  made  for  another  special  trade 
demand.  If,  during  the  warm  season,  no  greater  variations  in  the 
strength  occur,  no  appreciable  difference  in  the  product  made  therewith 
would  result. 
In  conclusion  it  may  be  stated  that  none  of  the  formulas  for  the 
fluid  extracts  require  any  special  or  expensive  apparatus  in  carrying 
tliem  out,  and  that  they  all  appear  to  have  been  so  arranged  as  to  induce 
the  pharmacist  to  make  this  important  class  of  preparations  himself; 
the  danger  of  injury  from  heat,  in  the  evaporation  of  the  dilute  per- 
colate, and  of  loss  of  activity  by  precipitation  in  the  flnished  product, 
have  both  been  over-estimated  by  writers  on  fluid  extracts,  whose 
papers  have  had,  perhaps  unintentionally,  a  tendency  to  deter  the 
pharmacist  from  trusting  himself  with  their  preparation,  and  led  him 
to  rely  too  much  on  the  reputation  and  supposed  superior  facilities  of 
the  wholesale  manufacturer. 
16 
