49°  Gleanings  from  the  German  J  our  rials.  {Am'o£"a89aarm' 
microbes  (cholera,  typhus)  will  be  destroyed.  In  using  hydrogen 
peroxide  10  cc.  of  a  10  per  cent,  solution  is  added  to  a  liter  of 
water. — {Cntrlbl.f.  Bakt  u.  Parasitenk.)  Apoth.  Ztg..  1890,  485. 
Coffee. — To  detect  spurious  coffee  in  presence  of  the  genuine 
beans,  J.  Samelsohn  places  a  number  of  the  beans  in  ether,  separa- 
ting at  once  those  beans  sinking  below  the  surface ;  if  these  be 
broken  open  along  the  groove  and  it  be  found  that  the  membrane- 
ous testa  is  missing,  the  artificial  product  is  unmistakably  recog- 
nized.— [Ztschr.  f.  angew.  Chem),  Apoth.  Ztg.y  1890,  502. 
Color  reaction  of  isocholesterin. — This  body  found  in  wool-fat  by 
E.  Schulze  will  give  the  following  test :  If  as  little  as  one  milligram 
be  dissolved  in  2  cc.  chloroform,  10  drops  acetic  anhydride  and 
two  drops  concentrated  sulphuric  acid  added  a  yellow  color  is  pro- 
duced, passing  after  a  time  into  a  reddish  yellow,  the  liquid 
also  showing  a  green  fluorescence. — Ztschr  f  Physiol.  Chemie., 
1890,  522. 
A  new  method  for  the  saponification  of  fats,  waxes,  etc. — The  fat, 
etc.,  is  dissolved  in  ether  and  an  alcoholic  solution  of  sodium 
ethylate  (C2H5ONa)  added ;  after  a  short  time  a  compact  precipi- 
tate forms  which  consists  of  the  sodium  soaps,  the  nature  of  which 
allow  a  rapid  filtration  and  washing.  For  100  to  150  gm.  fat  the 
sodium  ethylate  formed  by  dissolving  10  gm.  metallic  sodium  in 
150  to  200  cc.  absolute  alcohol  is  necessary,  although  it  is  prefer- 
able to  insure  complete  saponification  to  use  2  to  3  times  the  quan- 
tity of  sodium  dissolved  in  the  above  quantity  of  alcohol ;  it  is  also 
advisable  to  allow  twenty-four  hours'  time  for  the  saponification.  The 
very  difficultly  saponifiable  wool-fat  is  very  easily  saponified  under 
these  conditions.  Instead  of  preparing  the  sodium  ethylate,  metal- 
lic sodium  can  be  added  to  the  alcohol-ether  solution  of  the  fat ;  the 
sodium  becomes  coated  with  a  layer  of  soap,  which,  upon  agitation, 
easily  separates.  This  method  is  especially  adapted  to  the  study 
of  those  fat,  etc.,  constituents,  which,  after  saponification,  are  solu- 
ble in  ether,  the  small  quantity  of  soap  dissolving  in  the  ether  being 
removed  by  agitation  with  several  portions  of  water. — A.  Kossel 
and  K.  Obermuller,  Ztschr.  f  Physiol.  Chemie,  1890,  597. 
Detection  of  albumenoids. — Traces  of  albumenoids  may  be  detected 
by  exhausting  the  substance  to  be  tested  with  lukewarm  water,  fil- 
tering, evaporating  to  a  small  bulk,  adding  an  excess  of  potassium 
hydrate  and  some  copper  sulphate,  and  evaporating  to  dryness ;  the 
