AmAug.?Sarm*}  Abstracts  from  the  French  Journals.  387 
This  product  was  estimated  by  removing  the  uncombined  bro- 
mine in  a  current  of  dry  carbonic  acid,  and  calculating  the  iron  as 
the  sesquioxide  ;  the  bromine  and  chlorine  were  estimated  by  the 
method  of  H.  Rose;  that  is,  submitting  a  mixture  of  silver  bromide 
and  chloride  to  a  current  of  dry  chlorine,  and  calculating  the  bro- 
mide by  loss : 
Calculated. 
Fe2Cl2Br. 
Fe  =  27-05 
ci  =  38-65 
Br  =  34-30 
Found, 
27-25 
3909 
33 '61 
27-19 
38-69 
33-98 
27-13 
38-80 
34^3 
ioo-oo 
99*95 
99-86 
99-96 
The  crystals  are  green  by  reflected  light  and  perfectly  opaque ; 
the  system  of  crystallization  could  not  be  determined.  They  are 
very  deliquescent, and  very  soluble  in  water;  the  solution  in  the 
smallest  possible  quantity  of  water  is  accompanied  by  a  notable 
disengagement  of  heat.  Solution  in  ether  is  a  test  of  purity,  the 
protochloride  of  iron  remaining  undissolved.  It  is  also  soluble  in 
alcohol,  chloroform,  benzin  and  toluene ;  insoluble  in  carbon  bisul- 
phide. It  loses  some  bromine  at  ordinary  temperatures  and  at  the 
temperature  of  the  Bunsen  flame,  loses  nearly  all  of  it,  leaving  a 
residue  of  anhydrous  protochloride  of  iron. — M.  C.  Lenormand, 
in  Jour,  de  Pharm.  et  de  Chim.,  May,  1893,  p.  503. 
Solution  of  silver  nitrate  has  been  found  by  van  der  Spil  {Geneesh. 
tydsch.  von  Ned.  hid.,  through  Rev.  int.  de  bib.  med.,  June,  1893,  P- 
213)  to  become  gradually  less  clear,  if  the  glass  of  the  container  is 
of  poor  quality ;  that  is,  if  it  contains  considerable  alkali. 
Copper  sulphate  solution  will  undergo  the  change  from  the  same 
cause. 
Reduction  of  silver  nitrate  by  the  action  of  light. — M.  Roux  was 
led  to  investigate  this  subject  by  the  explosion  of  an  old  argentic 
solution,  for  which  there  seemed  no  cause.  He  introduced  into  a 
tube,  a  concentrated,  perfectly  neutral  silver  solution,  and  exposed 
it  to  the  light  in  the  presence  of  distilled  water.  After  several 
weeks,  the  silver  nitrate  was  reduced  to  metallic  silver,  a  gas,  giving 
all  the  reactions  of  oxygen,  was  disengaged,  and  the  solution  which 
had  been  neutral  presented  a  slightly  acid  reaction — probably  by 
the  following  equations  : 
2(AgN03)  =  2Ag  +  N205  +  O 
N205  +  H20  =  2NO3  H 
