oSob^eri9?o"''"  }  Current  Literature.  755 
more  accurate  results,  has  been  adopted:  The  culture  solution  is  of 
the  usual  type,  containing  cane  sugar,  asparagine,  and  various  salts 
in  water;  loo  Cc.  of  this  solution  are  placed  in  a  500  Cc.  flask,  the 
solution  to  be  tested  added,  and  the  whole  diluted  with  water  to  no 
Cc.  The  flask  is  plugged  with  cotton-wool,  sterilized,  and  cooled 
to  30°  C. 
A  suspension  of  fresh  pressed  yeast  is  made  containing  0.3  Gms. 
in  I  litre  of  sterile  water,  well  shaken,  and  i  Cc.  is  introduced  into 
the  culture  medium  with  a  sterile  pipette.  The  flask  is  placed  in  an 
incubator  at  30°  C.  for  eighteen  hours,  and  the  growth  is  then 
stopped  by  the  addition  of  a  little  formalin.  The  yeast  is  filtered 
off  through  a  weighed  Gooch  crucible,  washed  with  water  and 
alcohol,  dried  at  103°  C,  and  weighed.  The  increase  in  weight  over 
that  of  a  blank  determination  is  directly  proportional  to  the  vit- 
amine  solution  added.  The  "vitamine  number"  of  a  material  is 
defined  as  the  number  of  Mgms.  of  yeast  produced  by  the  addition 
of  its  extract  computed  to  i  Gm.  of  the  original  material  tested. 
A  discussion  of  the  method  is  given,  in  which  it  is  shown  that  the 
vitamine  to  be  tested  must  be  in  solution,  that  foreign  organisms 
present  in  the  yeast  offer  no  serious  handicap  to  the  working  of  the 
method,  and  that  the  usual  substances  present  in  vitamine  solu- 
tions do  not  accelerate  the  growth  of  the  yeast.  (From  The  Analyst, 
August,  1920.) 
Criticai^  Study  of  Mkthods  for  the  Detection  of  Methyl 
Alcohol. — A.  O.  Gettler  (/.  Biol.  Chem.,  42:  311-328,  1920). — The 
author  has  examined  fifty-eight  tests  described  in  the  literature  by 
employing  them  with  the  distillates  from  a  number  of  liquors  to 
which  known  amounts  of  methyl  alcohol  were  added  ranging  from 
nil  to  30  per  cent.,  in  addition  to  five  typical  confiscated  methyl 
alcohol  liquors — a  total  of  eighteen.  The  various  reactions  are 
divided  into  two  groups :  (A)  Those  in  which  the  methyl  alcohol  must 
be  oxidized  to  formaldehyde  before  testing,  and  (B)  those  in  which 
the  methyl  alcohol  is  tested  for  directly. 
On  the  whole,  the  former  class  yields  more  reliable  and  sensitive 
reactions,  and  is  subdivided  according  to  the  class  of  compound  with 
which  the  formaldehyde  reacts — e.  g.,  phenylhydrazines,  phenols, 
alkaloids,  proteins,  amines  and  miscellaneous  substances. 
The  most  satisfactory  and  sensitive  reactions  are:  (a)  Phenyl- 
hydrazine-ferric   chloride-hydrochloric  acid.    (6)  phenylhydrazine- 
