204 
NATURE 
[ DECEMBER 27, 1906 
ing to 45 per cent. over the Chamonix figures; it was 
increased during the prolonged stay at the observ- 
atory, and on descending to Chamonix it only 
partially fell to the level of the ventilation before the 
ascent, an excess remaining for many weeks. 
(2) Changes in ‘Absolute  Ventilation.’-—The 
importance of this series of calculations rests on the 
possibility of comparing these changes with those in 
the “real ventilation,’’ for it will be clear that if the 
views advanced by M. Vallot are sound, then such 
comparisons will indicate how far the augmentation 
in the “ real”’ values through extra thoracic enlarge- 
ment has sufficed to compensate for the diminution 
in the actual quantity of oxygen as the result of the 
diminished air pressure. In the case of M. Vallot, 
who by frequent visits and ascents was a “trained 
subject,’’ it appeared that the high altitude always 
caused on arrival at the observatory an immediate 
fall in the total value of the absolute ventilation; 
this fall, although not large, was quite distinct, so 
that the increased thoracic work was apparently in- 
sufficient to compensate fully for the diminution in 
the quantity of inspired oxygen caused by the lowered 
atmospheric pressure. This continued for some days 
of the residence in the observatory, and then gradually 
became almost inappreciable, the deficiency being de- 
creased by 50 per cent., indicating the gradual 
development of an acclimatisation compensation. As 
in the real ventilation, so here the descent to 
Chamonix was necessarily associated with an 
immediate and complete return to the normal con- 
dition. 
The case of M. de Goumoens is still more interest- 
ing because more marked. He is spoken of as the 
‘“ untrained ’’ subject, and in his case the ‘‘ absolute ”’ 
value of the daily ventilation immediately fell con- 
siderably more than in the case of M. Vallot. This 
considerable fall occurred in spite of the circumstance 
that the compensatory thoracic work had shown a 
very marked increase. The continued life in the 
observatory was in M. de Goumoens’s case associated 
with a much more notable adjustment of the absolute 
ventilation value than M. Vallot (the ‘‘ trained ”’ 
subject) showed, so that by the second week the 
deficit had diminished by 80 per cent. The descent 
to Chamonix was associated with the disappearance 
of the deficiency, but since the ‘‘real’’ value re- 
mained persistently increased, this caused the ‘‘ abso- 
lute ’”’ value to be so much that instead of a deficiency 
there was now an excess of 30 per cent. over the 
previous Chamonix figures. Hence it appears that 
the respiratory mechanism responds by a compen- 
satory increase, as regards mechanical work, when 
the subject is brought into a low atmospheric pres- | 
sure, that this response is immediate, but is at this 
high altitude insufficient, and that the degree of in- 
sufficiency is less in those who have frequently under- | 
gone the experience. A further compensatory increase 
is then gradually brought into play which adds to 
the total and makes the whole compensation more 
nearly adequate, but this does not, as the immediate 
one does, cease when the subject returns to lower 
levels. It would thus seem probable, although M. 
Vallot does not himself give any definite suggestions 
on this point, that the immediate adjustment is one 
involving the respiratory nerve centres, whilst the 
slow adjustment involves the actual framework of 
the thorax. 
The total change in respiratory ventilation value, 
whether ‘real’? or ‘‘absolute,’’ being itself 
brought about by either greater amplitude or 
greater frequency of respiration, it was necessary 
for M. Vallot to ascertain the share taken by each 
of these factors. The changes in frequency were 
NO. 1939, VOL. 75 | 
often very pronounced, but their periodicity and 
general character were so irregular that no direct 
relation between the real ventilation values and the 
frequencies could be ascertained. On the other hand, 
the results as regards amplitude were far more 
definite, and it would appear that this is the chief 
factor in the production of the compensatory effect. 
The details of the observations given by M. Vallot 
under this head need not be referred to, since their 
general character will be sufficiently indicated by the 
foregoing remarks. As regards the whole investi- 
gation, it will be evident that since several such series 
of experiments were undertaken, the researches de- 
scribed in this volume of the Annales indicate an 
immense amount of laborious and prolonged work, 
and M. Vallot is to be congratulated upon the solidity 
of the contribution which he has made to the physio- 
logy of respiration, and upon the pertinacity which 
he has displayed in his conduct of the whole inquiry ; 
this pertinacity, combined with a rigorous limitation 
of the inquiry to one issue, has resulted in genuine 
achievement. 
Two other short memoirs are bound up with the 
volume. The first of these deals with meteorological 
observations made on the Glacier de Téte-Rousse by 
M. Mougin and M. Bernard during the following 
periods :—August 1 to October 18, 1901; June 1 to 
October 10, 1902; and July 1 to October 13, 1903. 
The occurrence of rain, snow, dew, &c., is noted, and 
the daily temperatures, minimal and maximal, are 
tabulated. A series of special experiments was made 
as to the temperature of internal parts of the glacier- 
It appears from these that at a depth of 15 metres 
the temperature remained constantly at 0° C. through- 
out all the months of the year. 
The third memoir is one by M. Henri Vallot. In 
this the author gives some further particulars as to 
the method which he has employed for mapping out 
the details of the Mont Blanc summit with its ex- 
tensive glacier fields. 1h (Gis 
SUCCESS OF ANTI-MALARIAL MEASURES. 
WO reports recently issued prove in a striking 
manner that malaria may be stamped out by 
the application of scientific measures directed against 
the malaria-bearing mosquitoes. The first report 
deals with Ismailia.1 Malaria was introduced into 
Ismailia in 1877, and since 1886 nearly all the in-- 
habitants have suffered from the disease. In 1go01, 
on the initiative of Prince Auguste d’Arenberg, presi- 
dent of the Suez Canal Co., Prof. Ronald Ross was 
consulted, and, acting on his advice, a series of 
measures instituted which has had the welcome 
result of completely freeing Ismailia from malaria. 
These measures consisted in the destruction of mos- 
quitoes, principally by filling in and draining the 
pools and marsh land, or treating these with petro- 
leum where the Anopheles breed, concreting water 
courses, &c., and instructing the inhabitants and pro- 
tecting their household water supplies. This has 
been attained at an initial cost of 50,000 frances, and 
an annual outlay of 18,300 francs. 
These measures were commenced in 1903, and from 
that time the ordinary mosquitoes disappeared from 
Ismailia, so that mosquito nets are no longer neces- 
sary. Since the autumn of. that year not a single 
Anopheles larva has been found in the protected zone, 
and no fresh cases of malaria have occurred. The 
number of cases of malaria per annum in Ismailia 
has been as high as 2500, and in 1902. before the 
1 ‘Suppression du Paludisme a Ismailia."’ (Compagnie Universelle du 
Canal maritime de Suez, Paris, 1906.) 
