84 
Chemical  Notes. 
^m.  Jour.  Pharia^ 
Feb.,  1880. 
burn  in  a  stream  of  oxygen,  but  to  dissolve  in  hydro-fluoric  acid,  show- 
ing them  to  be  a  silica  compound,  the  correctness  of  which  conclusion^ 
was  subsequently  acknowledged  by  Mr.  Mactear. — Chem.  News. 
Production  of  Ozone ^  Test  for  Manganese  and  Cause  of  Hydrogen  Explo- 
sions.— At  the  meeting  of  the  German  Scientific  Association  for  1879,, 
held  at  Baden-Baden,  Sept.  19th  to  23d,  Prof.  Bottger  made  some 
observations  upon  the  above  subjects.  He  had  observed  that  if,  instead 
of  covering  small  sticks  of  phosphorus  half  their  length  with  water,, 
solutions  of  potassium  bichromate  were  used,  ozone  was  much  more 
readily  obtained.  Also  that  the  red  coloration  of  chemically-pure  fused, 
potassium  chlorate  caused  by  traces  of  manganese  compounds  was  ani 
extremely  delicate  test  for  manganese.  The  frequent  explosions  which 
take  place  in  the  preparation  of  hydrogen  by  the  action  of  sodium  upon 
water  he  thought  might  be  explained  by  the  assumption  of  the  forma- 
tion of  a  sodium  peroxide,  which,  in  liberating  oxygen,  formed  an* 
explosive  mixture  with  the  hydrogen. — Ber]  Chem.  Ges.^  xii,  p.  2187. 
On  a  Hydride  of  Silicium. — J.  Ogier  has  submitted  pure  silicon 
hydride  to  the  action  of  the  electric  discharge.  After  a  time  pure 
hydrogen  only  remains,  while  a  yellow  coating  is  formed  in  the  interior 
of  the  tubes.  This  on  analysis  proves  to  be  a  body  of  the  composition 
Si2H3,  a  subhydride  of  silicon,  corresponding  to  C2H3,  crotonylene.. 
When  moderately  heated  in  air  it  burns,  throwing  oft"  small  sparks.  It 
is  inflammable  in  chlorine  when  cold  ;  when  heated  cautiously  in  an 
atmosphere  of  hydrogen  or  nitrogen,  it  evolves  siliciuretted  hydro- 
gen. He  has  also  studied  the  action  of  the  electric  discharge  upon 
arsenijiretted  hydrogen  ;  it  also  forms  a  solid  hydride,  AS2H,  correspond- 
ing to  the  solid  phosphide  of  hydrogen,  P^H. — Comptes  Rendus^  Dec. 
22,  1879. 
Organic  Chemistry.  —  On  Solid  Hydrocyayiic  Acid. —  Messrs.  Les« 
coeur  and  Rigaut  have  made  some  studies  upon  the  solid  products 
which  separated  from  hydrocyanic  acid  solution.  They  remark  tha^t 
pure  hydrocyanic  acid  can  be  preserved  very  long,  and  it  is  usually  the 
presenc  eof  ammonium  cyanide  and  water,  which  changes  it  into  the 
solid  black  substance  called  azulmin.  A  trace  of  potassium  cyanide 
brings  about  this  decomposition  even  in  the  absence  of  water.  The 
black  mass  is  ordinarily  amorphous,  but  often  permeated  with  more  or 
less  transparent  crystals,  which  can  be  extracted  with  boiling  benzol. 
In  this  way  are  obtained  colorless,  lustrous  crystals,  which  easily  become 
