356 
Vleminckx's  Solution. 
/Am.  Jour.  Phartu. 
(     August,  1914. 
Mix  the  slaked  lime  with  the  sulphur,  and  add  the  mixture  grad- 
ually to  1750  c.c.  of  boiling  water.  Then  boil  the  whole,  under  con- 
stant stirring,  until  it  is  reduced  to  1000  grammes,  strain,  and  having 
allowed  the  solution  to  become  clear  by  standing  in  a  well-stoppered 
bottle,  decant  the  clear  brown  liquid,  and  keep  it  in  completely  filled 
and  well-stoppered  bottles. 
We  accordingly  made  up  one-tenth  of  this  formula  by  taring  a 
600  c.c.  porcelain  evaporating  dish,  adding  175  c.c.  of  water  heating 
to  boiling  and  then  slowly  adding  the  mixture  of  freshly  slaked  lime 
and  sulphur,  constantly  stirring  while  heating  until  the  weight  was 
reduced  to  100  grammes.  The  material  was  then  decanted  into  a 
4  oz.  cork  stoppered  bottle,  allowed  to  stand  until  the  next  day, 
filtered  and  assayed  for  total  sulphur  by  the  following  method: 
14  Measure  10  c.c.  of  the  clear  sample  in  a  100  c.c.  measuring 
flask  and  fill  to  the  mark.  Analyze  10  c.c.  aliquots  of  this  solution. 
Treat  with  3  c.c.  of  saturated  solution  potassium  hydroxide  or  so- 
dium hydroxide  solution,  following  by  50  c.c.  hydrogen  peroxide 
free  from  sulphates.  Heat  on  the  steam  bath  for  one-half  hour 
exactly  and  then  acidify  with  hydrochloric  acid,  precipitate  with 
barium  chloride  in  the  usual  way  in  boiling  solution,  and  finally 
weigh  as  barium  sulphate."  Of  course  multiplying  the  weight  of 
barium  sulphate  by  the  proper  factor  gives  the  quantity  of  sulphur 
and  this  multiplied  by  100  gives  the  percentage. 
We  ran  blanks  on  the  reagents  and  determined  the  quantity  of 
sulphate  present,  which  was  then  deducted  from  that  found  in  the 
actual  analysis. 
This  is  Avery's  method,  and  is  suggested  by  the  Association  of 
Official  Agricultural  Chemists  for  the  analysis  of  lime-sulphur  dips 
and  lime-sulphur-salt  mixture  (U.  S.  Dept.  Agr.  Bureau  of  Chem- 
istry, Bui.  107,  rev.  page  34)  ;  it  is  an  extremely  accurate  and  simple 
one  which  in  our  hands  yielded  remarkably  close  duplicates. 
We  also  analyzed  the  sample  for  total  sulphur  irr  solution,  mono- 
sulphur  equivalent,  thiosulphate  sulphur,  sulphate  and  sulphite  sul- 
phur, total  sulphide  sulphur  and  total  lime  (CaO)  in  solution  follow- 
ing the  method  in  U.  S.  Dept.  Agr.  Bureau  of  Chemistry,  Bui.  162, 
page  29,  but  seeing  no  advantage  over  the  Avery  method,  employed 
that  in  all  our  analyses  and  simply  determined  the  total  sulphur,  of 
which  the  above  sample  showed  the  presence  of  10.838  grammes  in 
100  c.c.  of  solution. 
