170 
Chemical  Notes, 
/  Am.  Jour.  Pharm. 
i      April,  1881. 
CHEMICAL  NOTES. 
By  Prop.  Samuel  P.  Sadtler,  Ph.D. 
Inorganic^  Chemistry. — On  the  Position  of  Boron  in  the  List  of 
Chemical  Elements, — A.  Etard  proposes  to  place  boron  at  the  head  of 
the  vanadium  family  of  elements,  forming  a  group  intermediate 
between  that  of  phosphorus  and  that  of  carbon.  This  juxtaposition 
of  boron  to  the  phosphorus  group  is  supported  by  the  existence  of  the 
compounds  BCI3  and  BOCI3,  recently  discovered  by  Councler  (this 
journal,  1879,  p.  124),  and  by  the  existence  of  boric  triethide,  or  tri- 
ethylborine,  which  is  analogous  to  triethylphosphine  iw  composition 
and  properties.  The  relations  of  vanadium  to  the  phosphorus  group 
have  been  established  by  E-oscoe,  and  the  labors  of  Deville  and 
Troost  have  done  as  much  for  niobium  and  tantalum.  Boron  and 
vanadium  are  both  grey,  pulverulent,  carbon-like  substances,  combus- 
tible and  infusible ;  both  combine  with  chlorine,  forming  BCI3  and 
VCI3,  and  their  oxy chlorides  BOCI3  and  YOCI3  are  yellow  fuming 
liquids.  Boron  and  vanadium,  like  the  other  members  of  the  group^ 
B,  V,  Nb,  Ta,  have  also  the  somewhat  rare  property  of  directly 
absor})ing  nitrogen.  The  author  will,  in  a  subsequent  communication^ 
describe  the  properties  of  an  oxide  of  boron,  B^Og,  corresponding  with 
YA  and  Vp,.—CompL  Rend.,  91,  627—629. 
Spontaneous  Combustion  Engendered  by  Nitric  Acid. — The  question 
whether  nitric  acid  is  able  to  cause  an  ignition  of  vegetable  tissue  has 
often  been  discussed,  without  apparently  having  been  settled.  K» 
Kraut  describes  some  experiments  which  seem  to  settle  this  matter  in 
the  affirmative.  Taking  a  square  wooden  box,  some  25  cm.  length  of 
side  and  about  40  cm.  high,  it  was  filled  15  to  20  cm.  deep  with  hay,, 
straw  and  sawdust,  and  upon  this  material  was  placed  a  small  flask 
containing  25  to  100  ccm.  of  nitric  acid,  of  at  least  1*5  sp.  gr.,  and 
then  the  space  above  filled  loosely  with  hay  or  straw.  The  flask  was 
then  broken,  and  a  wooden  cover  put  on  tightly.  At  the  end  of  one 
or  two  minutes  vapors  are  discernible,  and  in  a  few  minutes  more  a 
thick  white  vapor,  arising  from  the  decomposition  of  the  nitric  acid,, 
is  seen,  and  this  is  followed  by  the  smoke  from  the  burning  hay  or 
straw.  If  at  the  end  of  5  or  10  minutes  the  cover  of  the  box  be 
taken  ofl^",  the  interior  is  found  filled  with  glowing  coals,  which  blaze 
upon  contact  with  the  air,  and  frequently  set  the  box  itself  on  fire» 
Sometimes  the  inflaming  takes  place  without  any  removal  of  the  box 
