Pettenkofer and Voit1 observed the metabolism in an acute case of leukocythemia of four years' duration, and at a time four months before the death of the patient. There was one white to every three red blood-corpuscles, a high degree of anemia, and great physical weakness. The metabolism was exactly the same as in a normal resting man living under the same dietary conditions.

Magnus-Levy states that, rightly interpreted, these experiments of Voit indicate an increased metabolism. He2 found an increased metabolism in a case of severe pernicious anemia. Grafe3 reports a large increase in metabolism in leukemia. Roily,4 however, states that in chlorosis and in mild anemias there is no increase in metabolism in human beings.

Meyer and Du Bois5 made calorimetric observations upon 5 patients suffering from anemia. Direct and indirect calor-imetry agreed within 3 per cent, and the respiratory quotients ranged within the normal limits. The following table epitomizes their results:

Metabolism In Anemia In Man

These results show an increased metabolism in pernicious anemia which is especially pronounced when the hemoglobin content of the blood falls to 20 per cent, of the normal.

In Case III the legs were wasted and atrophic and could no longer be used. Of itself, this condition would have lowered the metabolism.

1 Pettenkofer and Voit: "Zeitschrift fur Biologie," 1869, v, 319. 2 Magnus-Levy: "Zeitschrift fur klinische Medizin," 1906, lx, 179. 3 Grafe: "Deutsches Archiv fur klinische Medizin," 1911, cii, 406. 4 Roily: Loc. cti.

5 Meyer, A. L., and Du Bois: "Archives of Internal Medicine," 1916, xvii, 965.

Meyer calculated for Case II that there were 3.7 c.c. of oxygen in 100 c.c. of arterial blood. If the patient had had a normal heart-beat of 70 per minute with an output of blood of 50 c.c. per beat, 130 c.c. of oxygen would have been carried to the tissues per minute. Iri fact, 252 c.c. of oxygen were absorbed by the patient each minute and his pulse-rate was 101. To have supplied enough oxygen for tissue respiration his output of blood per heart-beat must have been at least 66 c.c.

Another patient with lymphatic leukemia had a very high metabolism which was scarcely affected by vigorous x- ray therapy, although the lymphocytes were greatly diminished in number.1

The characteristic optical properties of human hemoglobin, its power to combine with between 1.33 to 1.35 c.c. of carbon monoxid gas per gram of substance, and its iron content of 0.33 to 0.34 per cent., are always constant, both normally and in diseases such as polycythemia, pernicious anemia, chlorosis, scurvy, and pseudoleukemia. This important fact, which shows that hemoglobin is not itself chemically changed in anemia, was demonstrated by Butterfield.2

In emphysema of the lungs in man determinations by Geppert and by Speck3 have shown that the respiratory exchange of gases was entirely within normal limits.

Carpenter and Benedict4 have found the metabolism of a man in whom the left lung was entirely obliterated to be unchanged from the normal.

It is evident from these various citations that the general oxidation of the body is normally maintained in anemia and in pulmonary disease, provided the disturbances are not of extreme intensity.

1 Means and Aub, unpublished.

2 Butterfield: "Zeitschritt fur physiologische Chemie," 1909, lxii, 173.

3 Cited by Jaquet: "Ergebnisse der Physiologie," 1903, ii, I, 562.

4 Carpenter and Benedict: "Journal of Biological Chemistry," 1909, vi, p. xv.

The constantly increasing use of mountain air as a recuperative force for the worn-out individual leads to the inquiry whether the metabolism at high altitudes is different from that at the sea-level. For knowledge of this sort we are principally indebted to Zuntz and his pupils. The study of the subject may be taken up by using three different methods: First, the pneumatic cabinet; second, balloon ascensions; third, mountain ascents.

The pressure of the atmosphere varies with the height from the sea-level as appears in the following table:

In a celebrated balloon ascension made by Tissandier and two companions in 1875 only Tissandier lived to tell the following tale:

At a height of 7000 meters Tissandier is unable to make the effort to remove his gloves from his pocket. All breathe oxygen. The temperature is - 11°. Sivel throws ballast. At 7500 meters the condition of torpor is extraordinary, but there is no suffering. The arms cannot be moved to reach for the oxygen tube. At 280 mm. barometric pressure Tissandier wishes to call out that the level of 8000 meters has been passed, but cannot speak. Consciousness is then lost. The height of 263 mm. barometric pressure is reached before the balloon begins to descend and, on recovery of consciousness, Tissandier finds that his two companions are dead.

In 1909 the Duke of Abruzzi, with several companions, ascended to a height of 7500 meters (= 24,600 ft, = 4.7 miles = 312 mm. Hg.) in the Himalayas, and although the physical conditions were extremely trying, they suffered no serious physiologic inconvenience. Douglas, Haldane, Henderson, and Schneider1 point out that this immunity was acquired by prior acclimatization during two months of residence at an altitude of 17,000 feet. The ascent of Mt. Everest, the highest mountain in the world (8840 meters = 29,000 feet = 5.5 miles), though perhaps physically unattainable, may not be physiologically impossible.

The relative composition of the atmosphere is the same at all distances from the earth's surface. Durig and Zuntz2 find that the atmosphere at a height of 2900 meters contains carbon dioxid 0.03 per cent., nitrogen 79.11 per cent., and oxygen 20.86 per cent., whereas at an altidude of 4600 meters it contains carbon dioxid 0.03 per cent., nitrogen 79.10 per cent., oxygen 20.87 Per cent. These are values practically identical with each other and with those determined at sea-level.