1901 - 2 .] The Condition of the Iron in the Spleen. 25 
fluid was decanted off, and the sediment washed by decantation, 
collected on a filter, washed first with water, then with alcohol and 
ether, and finally dried. This substance may be called Precipitate B. 
The fluid which had been decanted off was filtered, and then 
coagulated at a temperature of 70°-72° C. The resulting coagulum, 
when collected and treated just as in the previous case, constituted 
Precipitate C. 
The original filtrate from the half-saturation of the splenic 
extract with ammonium sulphate (Filtrate A) was then saturated 
by shaking up with crystals of the salt. A copious brown-coloured 
precipitate resulted, which contained the haemoglobin, the filtrate 
from this being almost colourless. This precipitate (Precipitate D), 
after solution in water, was coagulated by heat, and the brown 
coloured clot was thoroughly extracted by alcohol and ether (2 :1) 
containing 1 per cent, of oxalic acid. By this extraction the haematin 
was easily removed. Afterwards the coagulum was collected, 
washed and dried, and reserved for further examination for the 
presence of iron, as was also the case with the two substances— 
Precipitates B and C. 
It should be stated that in order to avoid any chance of error 
from the presence of haematin, Precipitates B and C were also 
extracted with the alcohol-ether-oxalic-acid mixture. 
These substances — Precipitates B, C, and I) — were suspended 
in water and then treated (1) with ammonium sulphide, which 
gave a black colour; (2) with hydrochloric acid and potassium 
ferrocyanide, the result being the development of Prussian blue ; 
(3) with hydrochloric acid and ammonium sulpho-cyanide, which 
gave the usual red reaction. 
These tests indicate the presence of iron in the proteid bodies 
obtained from the spleen by the methods already described. 
Each of the precipitates also gave a small quantity of ash, which 
on analysis showed the presence of iron. 
Finally, it may be mentioned that nucleo-proteid matter obtained 
from the spleen by Halliburton’s sodium-chloride method was also 
found to contain iron. 
Thus substances containing iron have been identified histologi- 
cally, and proteids containing iron have been separated by chemical 
methods. 
( Issued separately February 17, 1902 .) 
