DECEMBER 27, 1906| 
NATURE 202 
SCIENTIFIC WORK ON MONT BLANC.* 
‘|°HE sixth volume of these reports upon the 
observations made in the highest experimental 
station in Europe contains an account of some valu- 
able results obtained by the director, M. Vallot, as to 
the respiratory changes associated with prolonged 
residence at the altitude of 4350 metres. The observ- 
ations were begun at Chamonix in 1886; this pre- 
liminary inquiry led to extended experiments with 
improved methods mainly in 1898, 1899, and 1goo. 
The object of the inquiry was to ascertain the physio- 
logical condition, as regards respiratory efficiency, of 
an individual living for some little time in the observ- 
atory and carrying on his ordinary avocations. Many 
observations were made by M. Vallot upon himself, 
but these were supplemented by those obtained from 
a skilled collaborateur, M. de Goumoens. 
It cannot be said that this prolonged and 
laborious inquiry presents that extent of scope which 
was such a characteristic feature of the work carried 
out by Prof. Zuntz, but the results are in some 
respects quite as valuable as those of Zuntz and his 
colleagues; for, in the first place, they are trustworthy 
observations made during a prolonged sojourn at 
an altitude exceeding that of the Margherita Cabin 
on Monte Rosa, and, in the second place, the fact 
that they are confined to one narrow field gives them 
an additional scientific exactitude. It is undoubtedly 
an advantage, in any study of the exceedingly com- 
plex changes which the living organism undergoes at 
high altitudes, to focus the attention upon one point 
of fundamental importance. It is obvious that such 
a point is the total respiratory ventilation during a 
stay in high altitudes, for the modification of the 
respiratory acts is a familiar incident in the experi- 
ence of all those who have had the opportunity of 
reaching the summit of the higher Alps. Moreover, 
the detailed study of respiratory modification through 
diminished atmospheric pressure must be carried out 
before drawing any physiological conclusions as to 
the significance of those general metabolic changes 
which have been so ably brought forward by Zuntz. 
There is consequently a distinct gain in the concen- 
tration of effort displayed by M. Vallot. It is possible 
that the technique employed by him might be now 
improved; each succeeding Alpine investigator of a 
scientific character learns something from a_ pre- 
decessor, and this truth is plainly displayed in the 
account given by Zuntz already referred to, and in 
the more recent memoirs of Durig published this 
year in vol. cxiii. of the Archiv f. d. ges. Physiol. 
But the methods used by M. Vallot appear to be fully 
adequate to determine the special points which he 
brings forward, and the results undoubtedly reveal 
certain features of the respiratory mechanism of no 
little special and general interest. 
It is common knowledge that the degree of the 
pulmonary ventilation is continually changing, this 
being due to alterations both in the frequency and 
the amplitude of the respirations; but if the amount 
of the air breathed in and out is estimated during 
the whole of a considerable period, these variations 
practically disappear. It is thus possible to obtain 
a series of total volumes of pulmonary ventilation, 
each number in the series being that of some 
given period, such as an hour, or a day of 
twenty-four hours. The work described by M. Vallot 
consists in framing such series, both for himself and 
for M. de Goumoens, when resident in Chamonix, 
1 “Annales de l'Observatoire météorologique, physique et glaciaire, du 
Mont Blanc.” Tome vi. Pp. vii+2r8. Publiées sous la direction de J. 
ae Fondateur et Directeur de l'’Observatoire. (Paris: G. Steinheil, 
1905. 
NO. 1939, VOL. 75] 
during a prolonged stay in the Mont Blane Observ- 
atory, and again on return to the Chamonix level. 
His observations have thus been made continuously 
for considerable periods, and each period has com- 
prised the ascent to the observatory, residence there, 
and the return to Chamonix. On comparing the 
observations made respectively first at the low level, 
then at the high altitude, and finally at the low 
level again, certain differences are brought to light. 
In the first place, M. Vallot shows that his method 
is adequate to display the diurnal variations in the 
total pulmonary ventilation which occur at ordinary 
levels independently of the muscular exercise, and 
which are undoubtedly related to food assimilation. 
With regular meals and sound digestion these vari- 
ations occurred in the results obtained in Paris, and 
in Chamonix; their general character was a series of 
rises in the total amount of the hourly ventilation ; 
each rise came on after a meal, and lasted for a given 
period before it declined towards its old level. ‘These 
diurnal food variations in the pulmonary ventilation 
persist, according to M. Vallot’s observations, when 
the subject is living at a high altitude, and their 
character is unaltered provided the regimen of diet 
remains the same and there is no obvious impairment 
of the digestive system. ; f 
The most important part of the observations is, 
however, that which contains a series of the daily 
ventilation aggregates. In regard to these, M. 
Vallot considers them from two standpoints :— 
(1) that in which the aggregate volumes of the re- 
spiratory tidal air are measured at the temperature 
and pressure which they have in the lungs—this he 
terms the ‘“ real ventilation ’’; and (2) that in which 
the same aggregate volumes are all reduced to what 
they would be at 0° C. and 760 mm. Hg pressure— 
this he terms the ‘‘absolute ventilation.” The 
“real ventilation’? he takes as an index of the 
amount of the total thoracic enlargement, and thus 
of the mechanical work of respiration, whilst the 
‘‘ absolute ventilation’? he takes as an index of the 
quantity of air and of its oxygen component intro- 
duced into the lungs for the purposes of the organism. 
His general results may be briefly set forth under 
these two aspects. Pr 
(1) Changes in ‘‘ Real Ventilation.”’—All_observ- 
ations of an extended character on real ventilation 
quantities show in each individual occasional vari- 
ations occurring irregularly, and not accounted for 
either by muscular movements or, apparently, by food. 
These irregularities became far more conspicuous 
during prolonged residence in the observatory, and in- 
dicate that the organism, when in elevated regions, 1s 
in a condition of greater instability as regards its body 
processes; with due caution M. Vallot declines to give 
any more definite hint as to their meaning. If these 
irregularities are put on one side, the mean level of 
a whole series of daily aggregates is seen to be con- 
siderably affected by the high altitude of 4350 metres. 
The effect is a rise, which in M. Vallot (regarded as a 
trained subject) was immediate on arrival at the 
observatory; it amounted to a total daily increase in 
“ real ventilation” of 30 per cent. over the Chamonix 
figures. It was very slightly increased during the 
stay in the observatory, and immediately fell on de- 
scending again to the lower level. Tt was not the 
consequence of the muscular efforts involved in the 
ascent, and appears to have been a direct response of 
the organism to the lower atmospheric pressure ; 
there is thus an increase in the mechanical work of 
the thorax and lungs at high altitudes. ’ 
In the case of M. de Goumoens, who is described 
as an “untrained subject,’ this immediate rise in 
“real ventilation ’? was still more prominent, amount- 
