"3™'}   Methods  for  Analysis  of  Castile  Soap.  249 
Bibliography. 
1.  Kellerman,  Karl  F.,  Pratt,  R.  Winthrop,  and  Kimberley,  A.  Elliott. 
The  disinfection  of  sewage  effluents  for  the  protection  of  public  water  sup- 
plies. Bulletin  115,  Bureau  of  Plant  Industry,  U.  S.  Department  of  Agri- 
culture, p.  8,  1907. 
2.  Moore,  Geo.  T.,  and  Kellerman,  Karl  F.,  A  method  of  destroying  or 
preventing  the  growth  of  algae  and  certain  pathogenic  bacteria  in  water 
supplies.  Bulletin  64,  Bureau  of  Plant  Industry,  U.  S.  Department  of 
Agriculture,  1904. 
3.  Moore,  Geo.  T.,  and  Kellerman,  Karl  F.,  Copper  as  an  algicide  and 
disinfectant  in  water  supplies.  Bulletin  76,.  Bureau  of  Plant  Industry,  U.  S. 
Department  of  Agriculture,  1905. 
METHODS  FOR  THE  ANALYSIS  OF  CASTILE  SOAP.1 
By  Joseph  L.  Mayer. 
Castile  Soap  is  official  and  the  authorities  recognize  the  pharma- 
copoeia as  a  standard,  therefore  care  should  be  exercised  to  buy 
or  sell  an  article  which  is  true  to  name  and  is  an  olive  oil  soap. 
Aside  from  the  fact  that  the  sale  of  a  substitute  subjects  the 
seller  to  legal  prosecution,  its  use  causes  the  difficulty  so  fre- 
quently encountered  in  preparing  soap  liniment. 
As  many  soaps  sold  as  castile  are  not  what  they  are  labelled 
it  is  necessary  to  subject  samples  to  analysis  in  order  to  determine 
whether  they  are  properly  made  olive  oil  soaps. 
In  my  own  work  I  have  employed  the  following  methods  with 
excellent  results: 
Sampling. — Select  a  sample  which  is  representative  of  the  whole 
lot  or  bar.  If  in  the  latter  form  shavings  should  be  taken  from 
different  parts  such  as  the  outer  and  inner  surfaces,  and  after  being 
thoroughly  mixed  kept  in  a  tightly  corked  bottle  from  which 
samples  are  taken  for  analysis. 
Water. — The  method  of  U.  S.  P.,  that  is  taking  .500  gramme 
of  sample,  placing  in  a  previously  tared  beaker  containing  1  gramme 
of  sand,  adding  10  c.c.  alcohol  and  evaporating  to  dryness  and  then 
drying  at  no°  C.  to  constant  weight  is  entirely  satisfactory.  Care 
must  be  exercised  in  heating  to  conduct  the  evaporation  on  a  water 
bath  and  to  employ  a  small  flame,  otherwise  the  sand  will  be  very 
forcibly  ejected  from  the  beaker  and  the  determination  ruined. 
The  quantity  of  water  allowed  by  the  pharmacopoeia — 36  per 
1  Read  before  the  Kings  County  Pharmaceutical  Society,  May  13,  1913. 
