Am.  Jour.  Pharm.  ) 
August,  1920.  ) 
Current  Literature. 
investigations  of  the  Department  of  Agriculture  have  shown  that 
the  borates  were  to  blame.  The  salt  was  found  to  be  particularly 
inimical  to  germination.  The  manufacturers  of  the  Searles  Lake 
potash  have  recognized  the  danger  and  are  now  marketing  a  product 
containing  very  little  borate.  It  is  evident  that  any  new  source  of 
potash  will  have  to  be  carefully  examined  for  this  objectionable 
compound.  H, 
Rapid  Method  of  Estimating  Lkad  in  Cassia  Oii.. — O.  F. 
Lubatti.  (/.  Soc.  Chem.  Ind.,  39:  35-36T,  1920.) — Cassia  oil  ex- 
ported from  China  is  contaminated  with  lead  derived  from  the 
leaden  vessels  in  which  it  is  sold.  For  the  rapid  colormetric  esti- 
mation of  this  lead  by  means  of  ammonium  sulphide  5  Cc.  of  the 
oil  (or  2.5  Cc.  if  a  preliminary  test  has  indicated  the  presence  of  more 
than  0.025  per  cent,  of  lead)  are  diluted  to  about  23  Cc.  with  90  per 
cent,  alcohol  in  a  Nessler  cylinder  of  narrow  diameter  (2.5  Cm.). 
The  same  amount  of  cassia  oil  free  from  lead  is  diluted  in  the  same 
way  in  a  second  tube,  i  Cc.  of  ammonium  sulphide  solution  added 
to  each  liquid,  and  a  standard  solution  of  lead  in  90  per  cent,  alco- 
hol (i  Cc.  =  0.0001  Gm.  Pb)  is  added  to  the  blank  until  it  matches 
the  brown  coloration  of  the  sample  under  examination.  The  liquid 
is  stirred  three  times  after  each  addition  of  lead  solution.  The 
results  thus  obtained  are  slightly  high,  the  average  excess  being 
0.00018  Gm.  The  amount  of  lead  usually  present  in  commercial 
samples  ranges  from  0.04  to  0.06  per  cent.  In  a  test  experiment, 
in  which  a  pure  oil  was  left  in  contact  with  bright  lead  in  closed  tubes, 
which  were  shaken  at  intervals,  the  maximum  absorption  of  lead 
was  0.074  P^^^  cent.,  and  was  reached  after  one  month.  (From  The 
Analyst,  April,  1920.) 
Testing  the  Amylolytic  Action  of  the  Diastase  of  Asper- 
gillus Oryzae  (Taka-Diastase). — S.  A.  Waksman  (/.  Amer.  Chem. 
Soc.,  42:  293-299,  1920). — The  various  diastatic  enzymes  differ  in 
their  mode  of  action  towards  starch,  particularly  as  regards  the 
relative  quantities  and  rates  of  formation  of  the  intermediate  and 
final  products.  In  this  sense  it  is  convenient  to  differentiate  between 
the  amylolytic  (liquefying)  and  the  saccharifying  powers  of  the  com- 
mercial diastatic  preparations.  The  measurement  of  saccharifying 
power  has  formed  the  subject  of  many  exact  researches  but  the 
measurement  of  amylolytic  power  leaves  much  to  be  desired  in  the 
