432% 
had led Hrerr and BaArven to investigate the absorptive power of 
red blood-corpuscles for chloroform in chloroform-narcosis. These 
investigators found indeed that during the chloroform-narcosis the 
oxygen-percentage of the red blood-corpuscles is modified *). It was 
found to have increased. Because less oxygen is used? 
We began now by investigating, to what extent in an ordinary 
leneocyte-suspension i.e. without chloroform the phagocytosis depended 
on the oxygen-percentage of the medium. 
For these investigations no carbon was used, because, as we 
know, this substance possesses the property of absorbing gases to a 
considerable extent. Instead of it we made use of amylum of rice- 
flour. The technical part had been worked out by Dr. J. pr Haan, 
who, in consequence of the European war was prevented from 
completing his investigation. A detailed description of the technical 
part will, therefore, be published later on. 
The principle for determining the degree of phagocytosis was the 
same as that for the taking up of carbon. It was namely determined 
which percentage of the leucocytes counted, had taken up amylum 
after a certain time. 
I. Comparison of the extent of the phagocytosis in a NaCt- 
solution which had been treuted with nitrogen, with 
atmospheric aw and with oaygen. 
As regards the way in which the experiments were carried out 
the following may be observed. 
A thick suspension of horse-leucocytes in NaCl 0.9°/, is prepared 
in the manner we described before. *) 
Further a considerable volume of NaCl-sol. 0.9" , is boiled out, 
an increase in the concentration being obviated. 
a. part is treated with nitrogen. 
| att Re eee ,, atmospheric air. 
eae Cag ML Ls » Oxygen. 
Thus NaCl-solutions with increasing oxygen-percentages were ob- 
tained. We satisfied ourselves of this by oxygen-determinations accord- 
ing to the method of Winkier with manganous chloride, natrium- 
thiosulphate, hydrochloric acid and I in Kl. 1 cubic centimetre of 
the thiosulphate-solution corresponds with 0.0782 mmg. of oxygen. 
1) Hecer et Barucu. Instit. Solvay 13 Fasc. 1; Bulletin de Acad. Royale de 
Médecine de Belgique Séance du 26 Juillet 1915. 
2) Cf. inter alia. Physik. chem. Untersuchungen über Phagozyten. Wiesbaden, J. F. 
BERGMANN 1912, 
