Am.  Jour.  Pharir. ) 
Ju'y,  1879.  J 
Chemical  Notes. 
353 
upon  certain  mooted  questions.  Thus  it  was  not  certain  whether  the 
chloride  of  indium  had  the  formula  InCL  or  In2CI6,  whether  indium 
was  to  be  ranked  with  zinc,  with  an  atomic  weight  of  75*6,  or  with 
aluminum,  with  an  atomic  weight  of  113*4.  Only  a  determination  of 
the  vapor-density  of  one  of  its  well  characterized  compounds,  like  the 
chloride,  would  decide  this.    The  result  was  as  follows  : 
Calculated  vapor-density  for  In2Cl6,  15*20  ;  for  InCl3,  7*60  ;  experi- 
mental vapor-density,  7*87. 
The  formula  of  the  chloride  is,  therefore,  InCl3  and  not  In2Cl6,  and 
indium  does  not  belong  to  the  chemical  group  of  either  aluminum  or 
of  iron,  both  of  which  form  sesquichlorides. — Ber.  der  Chem.  Ges.y 
xii,  p.  6  1 1. 
Organic  Chemistry.—-  On  the  Oxydation  of  Resorcin  to  Phloroglucin. 
— Barth  and  Schreder  have  been  making  experiments  upon  the  phenols 
with  fusing  caustic  soda.  They  had  found  that  from  ordinary  phenol 
could  be  prepared  a  diatomic  or  even  triatomic  phenol  by  the  introduc- 
tion of  one  or  two  hydroxyl  groups  in  place  of  a  corresponding  number 
of  hydrogen  atoms,  and  they  applied  the  same  treatment  to  resorcin, 
C6H4(OH)2,  a  diatomic  phenol.  On  fusing  it  with  an  excess  of  com- 
mercial caustic  soda  in  a  silver  crucible,  the  light-yellow  fused  mass 
changed,  with  effervescing,  into  a  chocolate-colored  mixture.  The 
cooled  mass  was  put  in  dilute  sulphuric  acid,  and  after  the  separation 
out  of  some  brown  amorphous  flocks,  the  clear  brown  filtrate  was 
extracted  with  ether,  and  the  etherial  solution  allowed  to  crystallize. 
The  purified  crystals  were  found  to  be,  on  examination  and  analysis, 
phloroglucin,  C6H3(OH)3.  A  small  quantity  of  pyrocatechin, 
C6H4(OH)2,  a  diatomic  phenol  was  formed  at  the  same  time  from  the 
resorcin. — Ber.  Chem.  Ges.,  xii,  p.  503, 
On  Cantharidln  Derivatives. — J.  Piccard  makes  public  some  interest- 
ing results  obtained  with  this  relatively  little-studied  substance.  The 
change  of  cantharidin  into  cantharidinic  acid,  by  the  aid  of  hydrogen 
iodide,  he  rinds  to  depend  upon  the  formation  of  an  intermediate  iodine 
compound,  in  which  one  O  atom  is  replaced  by  two  I  atoms.  This 
compound,  when  boiled  with  concentrated  potassium  hydrate  in  a  sealed 
glass  tube,  yields  a  clear  oily  layer  of  pure  cantharen,  C8H12.  This  is 
much  purer  than  the  cantharen  obtained  by  heating  cantharidinic  acid 
with  caustic  potassa  to  4000  to  450°C.    It  boils  perfectly  constant  at 
