1 44  Gleanings  from  the  German  Journals.  {AmMa?ch,i892rm' 
hoi,  ether,  benzol ;  soluble  in  acetic  ether  and  nitro-benzol ;  if  only 
moistened  with  acetic  ether  there  is  produced  a  gelatinous  mass  ; 
nitro-jute  is  partially  soluble  in  ether-alcohol,  a  mixture  of  two 
parts  ether  and  one  part  alcohol  dissolving  11-93  Per  cent.;  the 
residue  is  only  slightly  soluble  in  acetone.  The  most  important 
difference  between  pyroxylin  and  nitro-jute  is  found  in  the  action 
of  alkalies  and  alkaline  carbonates,  nitro-jute  being  readily 
denitrated ;  to  deprive  the  product  of  the  acid  retained  after  wash- 
ing, a  dilute  (one  per  cent,  or  less)  and  cold  solution  of  sodium 
carbonate  gives  the  best  results. — Chemiker  Ztg.,  1892,  163. 
Impurities  of  chloroform. — In  the  fractional  distillation  of  a  large 
quantity  of  chloroform  (made  by  use  of  bleaching  powder)  it  was 
possible  to  separate  a  small  fraction  boiling  between  57  and  590  C, 
and  having  a  specific  gravity  of  1-185  >  tms  1S  believed  to  consist  of 
ethylidene-chloride  along  with  some  chloroform.  Other  impurities 
of  the  chloroform  give  rise  to  a  blue  or  violet  coloring  matter  upon 
agitation  with  sulphuric  acid ;  also  a  principle  developing  a  pepper- 
mint-like odor.  It  is  possible  by  prolonged  treatment  with  sul- 
phuric acid  to  remove  all  of  these  impurities  and  obtain  a  chloro- 
form which  in  no  way  is  inferior  to  the  chloroform  of  Pictet.  An 
important  matter  is  to  decide  between  such  pure  chloroform  and 
others  of  less  purity;  the  results  so  far  obtained  warrant  the  fol- 
lowing stringent  sulphuric  acid  test :  Equal  volumes  of  chloroform 
and  sulphuric  acid  (protected  from  light),  agitated  frequently  during 
six  to  eight  days  should  show  no  change  in  color  ;  after  the  chloro- 
form has  evaporated  spontaneously  from  the  separated  sulphuric  acid 
layer,  the  acid  diluted  with  five  parts  of  water  should  not  show  any 
change  upon  the  addition  of  1  cc.  JL.  silver  nitrate  solution.  This 
test,  it  is  needless  to  state,  will  only  be  complied  with  by  a  very 
pure  chloroform.  Another  test  which  promises  to  be  useful:  0  2  gm. 
metallic  sodium  and  5  cc.  chloroform  placed  in  a  glass-stoppered 
cylinder,  and  warmed  and  agitated  frequently  during  two  or  three 
days  will  give  the  following  results ;  with  a  pure  alcohol-free  chlo- 
roform there  is  no  change  to  be  noted  excepting  that  sodium 
chloride  separates  out  in  small  white  crystals.  The  presence  of 
alcohol  or  other  impurities  causes  a  more  energetic  reaction  and  the 
salt  separates  with  a  yellow  or  brown  color  ;  a  number  of  samples 
•of  chloroform  which  answered  the  requirements  of  the  German 
Pharmacopoeia  yielded  besides  the  colored  separation  of  the  salt,  an 
