AmAp°vt'Fgl8m'}    "Woody-Fiber"  in  Feeding-Stuffs.  285 
R.  Bensaude  and  M.  Terrey  {Presse  medicale,  igiy,  25,  168; 
Mar.  22)  recommend  a  gelatin  cream  containing  50  per  cent,  of 
barium  sulphate;  this  can,  they  say,  be  kept  without  any  tendency 
to  precipitation  for  a  long  time.  The  preparation  of  the  sulphate 
requires  great  care,  beginning  with  pure  recrystallized  barium 
chloride,  which  is  precipitated  completely  with  excess  of  sodium 
sulphate  ;  the  precipitate  is  then  washed  many  times  to  eliminate 
every  trace  of  chloride.  Incorporated  with  a  gelatin  medium  it 
forms  a  velvety  cream  in  which  the  barium  salt  is  so  finely  suspended 
that  it  deposits  very  slowly  indeed.  An  emulsion  containing  200 
Gm.  of  this  cream,  40  Gm.  of  syrup  of  acacia,  and  distilled  water 
to  250  Mils.,  may  me  made  without  trouble,  and  is  stable  for  several 
hours.  A  more  stable  emulsion  may  be  made  from  200  Gm.  of  the 
barium-gelatin  cream,  with  tragacanth,  5  Gm. ;  acacia,  2  Gm. ; 
glycerin,  40  Gm. ;  and  water  to  one  liter.  This  mixture  can  be  steril- 
ized and  when  a  deposit  forms  upon  keeping,  it  is  at  once  diffused 
by  agitation.  A  barium  meal  may  be  prepared  by  mixing  barium- 
gelatin  cream,  200  Gm. ;  with  powdered  soluble  chocolate,  50  Gm. ; 
powdered  agar,  10  Gm. ;  and  boiling  water,  150  Mils.  Very  good 
results  are  reported  from  this  preparation. 
THE  ESTIMATION  OF  "WOODY-FIBER"  IN 
FEEDING-STUFFS.1 
BY  J.  A.  VOELCKER  AND  E.  W.  VOELCKER. 
It  is  very  desirable  that  in  an  "  empirical "  method  of  analysis 
such  as  is  involved  in  the  estimation  of  woody-fiber  there  should  be 
agreement  as  to  the  strengths  of  acid  and  alkali  used  in  the  process. 
In  this  country  the  leading  agricultural  analysts,  following  the 
method  adopted  by  the  late  Dr.  Augustus  Voelcker,  F.R.S.,  use  2 
per  cent,  solutions  of  sulphuric  acid  and  caustic  alkali  for  the 
hydrolysis.  The  American  and  Continental  official  methods,  how- 
ever, prescribe  solutions  of  the  strength  of  1.25  per  cent,  only,  and, 
owing  to  the  unfortunate  tendency  in  this  country  to  favor  the 
adoption  of  foreign  methods  of  analysis,  these  find  their  way  into 
textbooks  and  are  liable  to  be  regarded  as  "  official "  here.  In  the 
case  of  such  feeding-stuffs  as  the  cereal  grains  and  their  offals, 
1  From  The  Analyst. 
