September 



1S97] 



NA TURE 



491 



Beatenberg. The present reputation of Alpine health j 

 resorts is, therefore, of comparatively recent date, \ 

 •especially so their use as places of residence during | 

 winter, and any one visiting Davos to-day would hardly i 

 believe that it is only about thirty-two years back since 

 the first invalids came there for their health. 



The French employ Alpine health resorts much less 

 than the English and Germans, and therefore Dr. Paul 

 Regnard is all the more to be congratulated on the 

 production of his capital book ; it is written in the clear 

 lucid style for which French scientific writers have be- 

 come celebrated, and it gives us a satisfactory explan- 

 ation of the principles on which the curative and ex- | 

 hilarating influences of residence in high altitudes ' 

 ■depend. The author carries us over the scientific ground ' 

 pleasantly enough, laying before us, in admirable order, 

 the various observations of practitioners, and the experi- ; 

 mental investigations which have been undertaken both ' 

 in the mountains and in laboratories to explain the action ' 

 of the phenomena observed. The result of all this work 

 is that the use of mountain climates is no longer 

 empirical, but rests on a well-established scientific basis. 

 One of the most interesting phenomena observed in 

 human beings and animals, when removed to high alti- 

 tudes, is the change which takes place in the quality of 

 their blood; and on this subject the author is well qualified 

 to speak, for much of the investigation concerning it has ' 

 been carried out by his compatriots, and he himself has | 

 undertaken several original experiments to settle doubtful | 

 points. I 



Paul Bert discovered that the blood of animals living | 

 in high altitudes absorbed more oxygen than that of I 

 similar animals at ordinary elevations, and in this ob- 1 

 servation he was soon confirmed by Miintz, who removed j 

 rabbits from Tarbes to the Pic du Midi de Bigorre in j 

 the Pyrenees (2377 metres), where they remained close | 

 to the observatory on the summit of the mountain, and ! 

 bred naturally. This was in 1883, and in 1890 Miintz \ 

 compared the blood of rabbits born on the mountains ; 

 with that of rabbits of the plain, and found that 

 the former was richer in haemoglobin, and absorbed j 

 more oxygen than the latter. Viault found that at ' 

 high altitudes the red corpuscles of the blood increased 

 rapidly in numbers, and out of proportion to the increase 

 in hicmoglobin. The work was taken up by Egger 

 and Mercier, of Arosa, and Prof Miescher, of Bale, and 

 no doubt was left that the red blood corpuscles notably 

 increased soon after residence in places of high altitude. 

 Egger found that the haemoglobin was likewise notably 

 increased, but not relatively so much as the number of 

 red corpuscles. When residents of the mountains 

 descended to live in the plain, he found that the 

 number of their red corpuscles fell to the normal. 

 Mercier considered that the degree of increase in the 

 number of corpuscles varied directly with the altitude. 

 Sellier tried the effect on animals of an atmosphere 

 abnormally rich in oxygen. His results were doubtful, 

 but the carefully conducted experiments of Regnard 

 himself seem to establish the fact that when animals 

 are kept for a considerable time in an atmosphere 

 containing too much oxygen, their red corpuscles 

 decrease in number. 



It is clear that Dr. Regnard assigns a great part of 

 NO. 1456, VOL. 56] 



the effect of mountain resorts to the influence of the 

 altitude on the blood. To illustrate his views, we may 

 take the case of a consumptive person. Hy life in town 

 and under other unhealthy influences, he has become 

 anaemic and badly nourished ; consequently his tissues 

 are less able to withstand the tubercle bacillus, and he 

 becomes infected. He then goes, we may suppose, to 

 some Alpine resort, either directly, or after resting some 

 time at an intermediate station. Owing to the diminished 

 amount of oxygen in the air at high elevations his blood 

 is not able to absorb enough for its proper requirements, 

 and consequently a " reaction " gradually takes place. 

 New "microcytes" are quickly formed, and these 

 develop rapidly into full-sized red corpuscles, and 

 gradually acquire the normal amount of hiemoglobin. 

 Thus the blood becomes richer in red corpuscles and in 

 hiemoglobin ; it can absorb more oxygen, and the whole 

 body is better nourished (though fat and comparatively 

 useless material may be lost, so that there may in many 

 cases be an actual decrease in body weight, at first at 

 least), and offers greater resistance to the growth of the 

 bacilli. When the patient descends to lower elevations 

 the number of his red corpuscles slowly returns to the 

 , normal amount ; the good eff^ects on the general nutrition 

 remain, and the blood, though not so rich in corpuscles 

 and hicmoglobin as it was in the mountains, is of good 

 quality and not below standard, as it probably was when 

 the illness commenced. 



Mountain sickness results, according to the author, 

 from the diminished pressure of oxygen in the atmo- 

 sphere, and its consequent diminution in the circulating 

 blood, at a time, moreover, when on account of the 

 muscular exertion of climbing it is especially needed. 

 It is, in fact, due to asphyxia of the tissues. Prof. 

 Clifford Allbutt and most authorities are practically now 

 agreed that deprivation of oxygen is the essential cause 

 of mal des inontagnes. 



The author believes that a comparative immunity from 

 phthisical contagion is obtained at high altitudes in spite 

 of the presence of phthisical patients and of the " con- 

 tagium vivum," which the more careless of them scatter 

 about with their expectoration. This he attributes partly 

 to the excellent ''sanguinification" of those resident in 

 high altitudes, and their consequent resistance to the 

 bacilli of tuberculosis, and partly to some antiseptic action 

 of the climate which is capable of diminishing the number 

 and virulence of these microbes outside the body. 



Though he points out the charms of mountain resorts, 

 Dr. Regnard is careful to speak of trials which some- 

 times await the visitor. It is in spring when the snow is 

 melting, that the Mediterranean resorts triumph, but 

 then succeeds the rapid growth of vegetation in the 

 mountains, one of the most beautiful sights afforded by 

 nature. The fogs which come with rainy weather cause 

 a moist cold which may be very trying, and these are 

 perhaps the chief drawbacks of the Alps. The dust of 

 the roads at some localities are amongst the drawbacks 

 which disappear during winter, when the ground is 

 covered with ice and snow. 



In the second part of the work, that chiefly devoted to 

 an account of the individual resorts, Dr. Regnard is 

 responsible for the new term "Hypsiatrie" {i.e. treat- 

 ment by high altitudes). The localities described have 



