288  Gleanings  from  the  German  Journals.  {Amju0nue^il>9iarm* 
one,  from  one  kilo  naphthalene  more  than  one  kilo  phthalic  acid  is 
obtained.  One  molecule  napthalene  requires  three  molecules 
potassium  bichromate  and  twelve  molecules  sulphuric  acid,  or  six 
molecules  sodium  chromate  and  fifteen  molecules  sulphuric  acid  for 
oxidation. — Dr.  H.  Luddens,  Chemiker  Ztg.,  1 891,  585. 
Tests  to  distinguish  naphthalene,  a-naphthol  and  fi-naphthol. — If 
O-i  gm.  of  these  substances  be  added  to  2  5  gm.  chloral  hydrate 
melted  in  a  test  tube  they  will  dissolve ;  naphthalene  colorless  (this 
remains  unchanged  in  the  subsequent  treatment)  a-  and  /9-naphthol 
pale  yellow ;  the  colors  do  not  change  by  standing  in  the  cold  but 
placed  in  a  water  bath  for  two  minutes  only  the  a-naphthol  changed 
to  a  red  violet ;  heating  for  two  minutes  more  the  /9-naphthol 
changes  to  blue  green  ;  heating  longer  in  the  water  bath  will  cause 
an  intense  ruby  red  with  a-naphthol,  and  with  /9-naphthol  a  pure 
blue  color  ;  these  tests  dissolve  in  an  equal  volume  of  alcohol  giving 
colored  solutions  free  from  fluorescence. 
II.  If  to  the  solution  of  these  substances  in  chloral  hydrate  five 
drops  hydrochloric  acid  were  added  a-naphthol  became  violet ; 
heated  in  a  water  bath  for  two  minutes  a-naphthol  became  dark 
green-blue,  /9-naphthol  intensely  yellow ;  naphthalene  with  this  test 
after  12  minutes'  heating  became  very  pale  red. 
III.  If  to  II  a  small  piece  of  zinc  be  added  there  will  result  with 
naphthalene  a  violet  color  changing  to  pale-brown  ;  with  a-naphthol 
a  dark  bluish-violet,  diluting  with  water  separates  a  coloring  matter 
giving  with  alcohol  a  red-violet  solution,  fluorescing  violet ;  with 
/9-naphthol  a  dark  brown  color,  diluting  with  water  separates  a  sub- 
stance giving  with  alcohol  a  yellow  solution  fluorescing  blue. — 
L.  Reuter,  Pharm.  Ztg \,  1891,  291. 
Test  for  resorcin. — o-i  gm.  resorcin  is  dissolved  in  §0  gm.  potas- 
sium hydrate  solution ;  upon  warming  a  few  cc.  of  this  solution  no 
change  takes  place,  the  addition  of  a  few  drops  of  chloroform  or 
bromoform  or  better,  a  few  crystals  of  chloral  or  bromal-hydrate, 
causes  an  intense  ruby  red  color.  This  test  was  also  tried  with 
napthalene  (remains  unchanged,  not  being  soluble  as  the  alkaline 
hydrate  solution),  a-naphthol  (dark  blue  changing  to  a  greenish 
blue),  and  /9-naphthol  (transiently  blue,  passing  into  yellow). — L. 
Reuter,  Pharm.  Ztg.,  1891,  292. 
Filicic  Acid  and  Extract  of  Male-fern. — L.  Reuter,  examining 
a  number  of  extracts  of  male-fern  finds  the  filicic  acid  to  be  quite 
