270 
Diffusive  Properties  of  Iron. 
Am.  Jour.  Pharm. 
May,  1880. 
The  following  table  will  show  the  principal  results  of  dialysis  in  the 
preceding  four  experiments  : 
Ten  per  cent.  Solutions  (200  grains  of  Ammonio- Citrate  of  Iron  in  2,000 
grains  of  Solution)  Dialy%ed  for  Six  Days. 
Amount  of  Per  cent,  of  Percent  of  Diffusion  Per  cent,  of  Fe203 
salt  salt  FeoQo  in  on  sixth  in  salt 
diffused,  diffused.  dift'usate.  d^y.  not  diffused. 
(2,  a)     150*38  75'i9             28-2  not  ended  6i'6i 
{2,  b)     146-30  73"i5             29-5  not  ended  52*48 
(2,         123*71  61-85             32'7  ended  69-49 
(2,  d)    iio*2o  55'io            35-5  ended  6S-38 
Having  observed  that  diffusion  stopped  when  the  salt  in  the  dialyzer 
became  highly  basic,  and  that  the  diffusate  as  well  as  the  contents  of 
the  dialyzer  became  more  and  more  basic  as  the  process  proceeded, 
results  which  I  shall  have  to  refer  to  hereafter,  I  thought  that  probably 
by  starting  with  a  salt  containing  less  than  the  usual  proportion  of  oxide 
of  iron  the  diffusion  might  be  carried  further  than  it  had  been  found 
possible  to  carry  it  in  the  preceding  experiments. 
I  obtained  a  good,  well-scaled,  neutral  and  perfectly  soluble  sample 
of  ammonio-citrate  of  iron,  containing  only  25*92  per  cent,  of  Fe203. 
10  per  cent,  and  5  per  cent,  solutions  of  this  salt  were  submitted  to 
dialysis,  in  the  way  already  described,  and  the  results  obtained  are  given 
an  the  following  tabulated  statements  : 
(2,  e.) — 10  per  cent.  Solution. 
Amount  of  Per  cent,  of  Per  cent  of 
Days,                                        salt  salt  FeoO.3  in  dried 
diffused.  diffused.  diffusate. 
2           .              .    92-23  grs.  46-10  21-56 
2  .              .           30-62  15*31  32-23 
3  ■  .  23-37  11-68  33-13 
3    .              .             8-16  4-08  35'5o 
3  .  .      2-27  1-13  3740 
4  •  .  *55  '27  39"43 
At  the  end  of  twenty-eight  days,  diffusion  having  stopped,  the  sale 
still  left  in  the  dialyzer  was  found  to  contain  61*26  per  cent,  of  FcgO.^. 
(2,  e.) — 5  per  cent.  Solution. 
Amount  of 
Per  cent,  of 
Per  cent,  of 
Days. 
salt 
salt 
FeoOs  in  dried 
diffused. 
diffused. 
diffusate. 
-2 
66-65  grs. 
33"32 
25-07 
2 
25-73 
12-86 
30*12 
3 
.  i7'9i 
8-95 
32-44 
3  . 
6-4 
3"2 
35-88 
3 
2-47 
1-23 
36-01 
4  • 
I  -64 
-82 
38-94 
6 
I-I4 
•57 
40-01 
At  the  end  of  twenty-eight  days,  diffusion  having  stopped,  the  salt 
in  the  dialyzer  was  found  to  contain  68*54  per  cent,  of  FegOg. 
