886 
Current  Literature. 
Am.  Jour.  Pharm. 
Dec,  1918. 
reflux  condenser,  evaporate  to  dryness  and  redissolve  in  25  Cc.  of 
water.  Shake  this  solution  out  with  ether,  wash  the  ether  with 
water  and  return  the  washings ;  dihite  to  about  950  Cc.,  add  10  Cc. 
of  dilute  sulphuric  acid,  and  make  the  volume  up  to  1,000  Cc.  Mix 
100  Cc.  of  this  with  10  Cc.  of  AT/io  potassium  bromate  solution,  1 
Gm.  of  potassium  bromide,  and  5  Cc.  of  sulphuric  acid.  After  15 
minutes  add  1  Gm.  of  potassium  iodide,  stand  for  5  minutes,  and  ti- 
trate with  N/i o  sodium  thiosulphate.  Not  more  than  6.5  Cc.  should 
be  required.  1  Cc.  N/10  potassium  bromate  solution  corresponds  to 
0.00/4  Gm.  of  cinnamic  acid.  (Schweiz.  Apotheker  Ztg.,  1918,  p. 
286.    Through  the  Pharmaceutical  Journal  and  Pharmacist.) 
Classification  of  Bacteria  as  to  Diastase  Production. — 
During  the  last  two  years  in  the  Dairy  Bacteriology  Laboratory  of 
the  University  of  Illinois  the  use  of  potato  slants  for  the  determina- 
tion of  diastase  production  by  bacteria  has  been  replaced  by  a  simple 
plate  method  as  follows :  A  starch  agar  is  made  by  adding  0.2  per 
cent,  of  water-soluble  starch  to  the  regular  plain  agar.  This  starch 
agar  can  be  sterilized  in  the  autoclave  along  with  other  mediums. 
Some  hydrolysis  takes  place,  but  not  enough  to  interfere  with  the 
test.  The  agar  is  poured  into  Petri  dishes  and  allowed  to  cool, 
when  a  stroke  2  inches  long  is  made  with  a  loopful  of  an  agar  slant 
growth  of  the  organism  to  be  tested.  The  plates  are  incubated  for 
two  days  at  370  C.  and  five  days  at  200  C,  after  which  they  are 
flooded  with  a  saturated  solution  of  iodine  in  50  per  cent,  alcohol. 
A  clear  area  about  the  stroke  averaging  more  than  2  mm.  in  width 
classifies  the  diastatic  action  as  strong,  while  a  width  of  2  mm.  or 
less  marks  it  as  feeble  and  the  absence  of  a  halo  as  absent.  (P.  W. 
Allen,  Urbana,  111.  Journal  of  Bacteriology,  Baltimore.  Reprinted 
from  The  Journal  of  the  American  Medical  Association.) 
Urine  Staining  Technic. — Minerbi  heats  the  isolated  urine 
sediment  with  human  blood  serum  or  egg  albumin,  both  of  which 
coagulate  under  the  action  of  fixation  measures.  Then  when  the 
May-Grunwald-Giemsa  stain  is  applied,  the  background  is  homo- 
geneous and  colorless,  and  the  preparation  is  exceptionally  instruc- 
tive in  every  respect.  After  centrifugating  the  urine,  all  the  fluid 
is  decanted  except  one  or  two  drops.  Then  a  droplet  of  egg  al- 
bumin is  taken  up  on  a  platinum  loop  and  the  loop  is  plunged  into 
the  sediment  and  agitated  to  mix  it,  with  care  not  to  cause  produc- 
