1 8  4  Albuminate  of  Iron.  { ^  Vp 
Process. 
Liq.  F'e 
U.  S.  Ph. 
sp.  gr.  1-355 
=  12-8  p.c.  Fe 
rri  Chlor. 
Phar.  Ger. 
sp.  gr.  1-480 
=  15  p.  c.  Fe 
Natural 
Egg-white 
(taken  to  contain 
12  5  p.  c.  dry- 
albumen. 
Dry 
Egg-albu- 
men 
Excess  of 
dry  egg-  al- 
bumen di- 
rected. 
Excess  of 
Liq.  Ferri 
Chlor., 
U.  S.  P., 
directed. 
Gram. 
Gram. 
Grams. 
Grams. 
Grams. 
Gram. 
Theory, 
I  'O 
0-854 
3-669 
Friese's, 
i*o 
0-854 
2-628 
0-341 
0-907 
Bernbeck's, 
I'O 
0-854 
2-8oo 
0  350 
0-9047 
BiePs, 
I'O 
0-854 
3*570 
0-0272 
Merck's, 
TO 
0-854 
3-410 
0  0908 
Donitz's,  <2, 
I  o 
0-854 
40-960 
5*120 
I  451 
Donitz's, 
I'O 
0  854 
82-000 
10250 
6-581 
Hager's, 
I'O 
0854 
1-640 
0-205 
09442 
Diehl's, 
I'O 
0-854 
29'03o 
3-629 
O'OI  I  I 
An  examination  of  the  table  will  make  it  clear  that  in  Friese,  Bern- 
beck's  and  Hager's  process  the  quantity  of  ferric  chloride  is  largely  in 
excess  of  that  required  to  form  an  albuminate  ;  that  Donitz  directs  a 
considerable  excess  of  albumen  when  the  smaller  quantity  {a)  of  the 
latter  is  employed,  and  a  very  large  excess  when  the  larger  quantity  {b) 
is  used  ;  while  Biel  and  Merck,  whose  processes  are  based  upon  the 
direct  combination  of  ferric  chloride  and  albumen,  direct  proportions 
that  agree  well  with  that  theoretically  required.  The  quantity  used  by 
me  corresponds  still  more  closely  with  that  required  by  the  formula 
provisionally  accepted,  and  the  proportion  having  been  arrived  at  experi- 
mentally, before  any  calculation  of  the  required  quantity  was  made, 
seems  to  support  the  view  that  in  the  formation  of  albuminate  of  iron 
I  molecule  of  ferric  chloride  and  i  molecule  of  albumen  are  concerned. 
The  large  excess  of  ferric  chloride  used  by  Hager  is,  as  has  been  shown, 
unnecessary,  and  was  probably  adopted  by  him  without  proper  reflec- 
tion. That  employed  by  Friese  and  Bernbeck,  however,  seems  to 
have  been  arrived  at  by  practical  observation,  and,  inasmuch  as  I  had 
failed  to  obtain  precipitates  by  the  direct  action  of  solution  of  ferric 
chloride  upon  egg-white,  if  the  latter  was  at  all  diluted  with  water,  the 
following  experiments  were  made  to  throw  some  light  upon  this  sub- 
ject, as  well  as  upon  some  points  embraced  in  the  foregoing. 
7.  To  204  grains  of  egg-white,  beaten  to  destroy  stringiness,  75 
minims  of  liq.  ferri  chlor.,  U.  S.  P.,  (corresponding  to  Friese's  method 
