390 
Tinctura  Ferri  Chloridi, 
f  Am.  Jour,  Pharm. 
t    August,  1883. 
Attention  was  now  directed  to  the  action  of  sunlight  on  the  tincture 
and  aqueous  solution  of  iron ;  for  the  latter,  Liquor  ferri  chloridi  35 
parts  was  mixed  with  distilled  water  65  parts.  The  specific  gravity  of 
this  solution  was  1*100;  it  was  of  a  yellowish-brown  color,  slightly 
lighter  than  the  tincture.  On  analysis  with  potassic  permanganate 
solution,  the  amount  of  iron,  etc.,  present  was  found  to  be  as  follows : 
Percentage  of 
6 
'2 
d 
d 
total. 
a 
'5 
a 
in  liqi 
i+12H2 
Q 
IM 
Iron, 
Iron 
Iron 
Iron. 
O 
5 
IM 
cc. 
Tincture,5  gm 
55-8 
•299546 
•023896 
•27565 
5-513 
15-9807 
26  -600^ 
Aqueous  solu- 
tion, 5  gm.... 
47-7 
•256049 
•023896 
•232153 
4^64402 
13- 4639 
2VUSi 
Liq.  ferri  chlo. 
(U.  S.  P.), 
1-390,  2  gm  
53-8 
•28929 
•023896 
•265394 
13-2697 
38-0511 
63 •334 
Three  specimens  each  of  the  alcoholic  tinctures  and  aqueous  solu- 
tions were  then  exposed  to  the  action  of  the  sun's  rays  for  various 
lengths  of  time.  The  alcoholic  tinctures  were  found  to  change  to  a 
greenish-brown  or  blackish-green  color,  according  to  the  duration  of 
exposure,  from  partial  reduction  to  ferrous  chloride,  while  in  both 
color  and  composition  the  aqueous  tincture  remained  unchanged.  The 
appended  table  shows  the  amounts  of  ferrous  salt  reduced  by  the  ac- 
tion of  sunlight  from  the  ferric  state. 
Exposure. 
KsMngOg. 
Iron  in 
ferrous  state. 
Iron  in 
ferric  state. 
Per  cent, 
of  ferrous 
iron. 
Aqueous  solution,  2, 4,  and  6  weeks 
23-5 
3Vi 
48^3 
None. 
•126195 
•168618 
•259371 
None. 
•149455 
•107032 
•016279 
45-79 
60-909 
94^054 
