602 PHYSIOLOGY OF ALPINISM 



heights brings about an actual increase in the total haemo- 

 globin is a view adopted by many authors. Thus, for ex- 

 ample, C. Foa holds that there is new formation of red 

 blood cells, with a heightened activity of the bone marrow. 

 Durig believes a final decision of the question will not be 

 had until our methods of determining the total haemoglobin 

 and the total capacity of oxygen combination are perfected ; 

 he calls attention to the fact that chlorosis is not cured by 

 high climate without appropriate treatment of other char- 

 acter, and that we do not find after return from the eleva- 

 tion the least increase of iron elimination and not a sign 

 of jaundice, as would be probable were there any massive, 

 important destruction of red blood cells. 



Then, too, within recent times, sources of error of which 

 we had no idea before, have come to be recognized. Thus 

 Biirker was able to prove that the hitherto commonly used 

 counting chamber of Zeiss gives too high results at a high 

 elevation, from the concentration of the blood from increased 

 evaporation. Biirker has constructed a new chamber by 

 which this error is avoided. With the latter he found at an 

 elevation of 1800 metres only a minor increase of the 

 erythrocytes, of not above five per cent. 0. Cohnheim and 

 his associates, in their most recent investigations in the 

 Monte Eosa district, conducted with great precision and 

 with the employment of various methods, at elevations of 

 2900 and 4500 metres have failed to recognize in human 

 beings and in the dog any physiologically important in- 

 crease in haemoglobin. 55 



Changes in Cardiac Activity. As is well known, dis- 

 turbances in connection with the cardiac activity are promi- 

 nent features in the symptom complex of mountain sickness ; 

 and it is not always easy in these very cases to rule out the 

 factors connected with over-exertion. Durig, Zuntz, and 

 their associates, found the pulse rate practically unchanged 



W O. Cohnheim, G. Kreglinger, L. Tobler and 0. H. Weber, Zeitschr. f. 

 physiol. Chem., 78, 62, 1912; cf. therein the Literature. 



