854 
ON  THE  VALUE  OF  DIFFERENT  KINDS  OF  SOAP. 
might  be  used  in  equivalent  quantity,  but  not,  I  think,  without 
disadvantage.  By  using  the  solution  of  sp.  gr.  '880,  which  very 
nearly  corresponds  with  the  stronger  solution  of  the  Pharma- 
copoeia, we  are  enabled  to  convey  to  the  sesquicarbonate  the  re- 
quired quantity  of  ammonia  without  adding  so  much  water  as  to 
liquefy  any  portion  of  the  salt,  and  without  danger  in  conduct- 
ing the  process.  It  may  not  be  out  of  place  to  mention,  as  a 
precaution,  that  the  strongest  Liquor  Ammonice  boils  at  a  tem- 
perature below  70^  Fahr.,  so  that  considerable  care  is  necessary 
in  using  large  quantities  of  this  solution,  and  also  in  preserving 
the  store  bottles  in  a  cool  place. 
In  the  third  volume  of  the  PharmaceuticalJ  ournal,  at  p.  265^ 
a  formula  is  given  for  Preston  salts,  which,  I  believe,  is  very 
commonly  adopted.  It  is  to  fill  the  bottles  with  sesquicarbonate 
of  ammonia  in  small  pieces,  and  then  to  add  one  drachm  of  vol- 
atile essence  to  each  bottle.  Now,  Preston  salt  bottles  hold,  as 
nearly  as  possible,  one  ounce  of  sesquicarbonate  of  ammonia, 
which  quantity,  I  think  I  have  shown,  would  require  nearly  five 
drachms  of  strong  solution  of  ammonia  to  convert  it  into  neutral 
carbonate.  The  common  method  of  adding  volatile  essence  or 
strong  solution  of  ammonia  to  the  sesquicarbonate  at  the  time  of 
filling  a  smelling-bottle  for  immediate  use  is  subject  to  two  ob- 
jections ;  first,  that  the  solution  is  not  thus  added  in  sufiicient 
quantity;  and  secondly,  that  the  ingredients  are  not  confined  to- 
gether for  a  sufficient  length  of  time  to  ensure  their  union,  before 
the  bottle  has  been  frequently  opened,  and  much  of  the  ammonia 
allowed  to  escape.  In  the  process  I  have  recommended  these 
objections  are  obviated,  and  a  product  is  obtained  which  is  fit 
for  immediate  use,  and  which  is  volatile  and  pungent  almost  as 
long  as  any  of  the  salt  remoim^.— London  Pharm.  Journ.  May^ 
1861. 
ON  THE  VALUE  OF  DIFFERENT  KINDS  OF  SOAP. 
By  R.  Graeger. 
Complaints  of  consumers  in  regard  to  the  value,  or  rather 
efficacy,  of  samples  of  soap,  which  to  the  best  of  the  manufac- 
turer's knowledge  have  been  well  prepared,  are  not  uncommon. 
