ON  THE   OILY  SUBSTANCE  IN  CHLOROFORM. 
113 
and  persons  from  fourteen  to  eighteen  years  of  age,  should  commence 
with  six  drops,  and  increase  as  above.  Children  from  one  to  two 
years  of  age,  to  commence  with  one  drop  ;  from  two  to  five  years, 
two  drops,  and  increase  one  drop.  The  usual  interval  with  us  is 
three  hours  between  the  portions.  In  ordinary  cases  of  pneumonia 
we  usually  continue  it  three  days  after  the  symptoms  are  subsided. 
In  typhoid  fever,  and  many  other  diseases,  it  requires  to  be  con- 
tinued longer.  For  the  satisfaction  and  information  of  the  profes- 
sion, we  would  state  that  it  may  be  continued  indefinitely,  in  mo- 
derate doses,  or  short  of  nausea,  without  the  least  inconvenience." — 
Southern  Med.  and  Surg.  Journ.,  Jan.  1853,  page  35. 
Dr.  Norwood's  other  papers  will  be  found  in  the  same  Journal, 
for  1850-51-52. 
UNITED  STATES  DISPENSATORY— AN  ERROR. 
To  the  Editor  of  the  American  Journal  of  Pharmacy. 
Dear  Sir  : — A  small  error,  it  seems,  has  managed  to  find  its  way 
into  the  late  (9th)  edition  of  the  Dispensatory,  and  as  I  have  seen  no 
mention  of  it  elsewhere,  I  avail  myself  of  this  means  of  calling  at- 
tention to  the  fact,  that  pharmaceutists  and  others  having  copies 
of  this  almost  indispensable  commentary  on  the  American  and 
English  Pharmacopoeias,  may  correct  the  same.  It  occurs  at  page 
1262  in  the  formula  for  Unguent um  Hydrargyri  JMitratis  of  the 
U.  S.  Pharmacopoeia  ;  the  quantity  of  nitric  acid  is  eleven  instead  of 
fourteen  fluid  drachms.  Prior  to  the  late  revision  of  our  National 
Codex,  eleven  fluid  drachms  of  the  then  officinal  acid,  having  the 
specific  gravity  1*5,  was  used  ;  but  at  that  time  the  standard  acid 
was  changed  from  the  sp.  gr.  1*5,  to  the  more  natural  strength  hav- 
ing the  sp.  gr.  1*42 ;  and  of  this  acid,  fourteen  measures  are  about 
equal  in  the  amount  of  real  acid  they  contain,  to  eleven  measures 
of  the  stronger. 
Richmond,  January  11,  1853.  Jos.  La  idle  y. 
ON  THE  NATURE  OF  THE  OILY  SUBSTANCE  EXISTING  IN 
COMMERCIAL  CHLOROFORM. 
By  Henry  Pemberton. 
In  order  to  ascertain  whether  the  use  of  common  whiskey,  in 
the  preparation  of  chloroform,  caused  the  formation  of  any  sub 
10 
