CHOLERA. 507 



formed the places of refuge for fugitives from cholera. Now and then 

 an epidemic occurs in the mountains ; these exceptions will be dealt 

 with later. The immunity, or the slight susceptibility, of mountain- 

 ranges for cholera is witnessed in India as plainly as it is in Europe. 

 A familiar example is the complete freedom from cholera of the hill- 

 stations along the Himalayas, in which, through frequent changes of 

 troops, the cholera has every chance of being taken up from the plains. 

 In the severe epidemic of 1869 there were only two cases of cholera in 

 nineteen hill-stations. A similar experience is met with in narrower 

 areas. For instance, in Munich, 1873-'74, the frequency of cholera 

 was widely different in the seven barracks of the garrison. In the low- 

 lying Isar Kaserne (occupied by cuirassiers, heavy cavalry regiment), 

 out of one thousand men there were forty cases of cholera ; in the high- 

 lying Max II Kaserne (with two field-artillery regiments) only three 

 cases, and this without there being any difference in the construction 

 of the caserns, the occupation or the diet of the men, or the drinking- 

 water. Another local factor, which is also very evident, is the nature 

 of the soil. Where the soil is compact, and not, or very slightly, per- 

 meable for water and air, the development of cholera is much hin- 

 dered. Some time ago Jameson, in his description of the epidemics of 

 1817 and 1819 in India, said, " Cholera does not appear to like a rocky 

 soil." French epidemiologists (Boubee and others) have said the same 

 thing. I studied this point in Bavaria in 1854, and then collected so 

 many facts that I came to the conclusion that cholera requires for its epi- 

 demic development a porous soil through which air and water easily 

 percolate, and that a compact soil was decidedly inimical. It will be 

 sufficient to give a couple of illustrations. When the cholera broke 

 out in Munich the inhabitants scattered themselves on the mountains. 

 Many settled in the valleys, where several fell ill and died. The 

 greater part of the town in which the better hotels were situated lies 

 upon compact chalky soil, and the smaller part was built upon alluvial 

 soil. In this part the cholera assumed an epidemic character. In the 

 higher-lying districts (Schrodelgasse) the epidemic began in the be- 

 ginning of August, and in the lower lying areas toward the end of 

 September, while the greater part situated on chalk was not affected. 

 Among the Jura Mountains to the left of the Donau lies a village 

 called Kienberg, which is built on rock. In this village the cholera 

 broke out so fiercely that within a month thirty per cent of the in- 

 habitants died. When I went there I found many houses emptied, 

 while other houses had not had a single case of illness. I then 

 thought that the drinking-water was at fault. But the whole village 

 drew water from a single spring at the foot of the slope on which the 

 village was situated. From a study of the soil I found that all the 

 houses built upon porous and rather loamy sand had been attacked, 

 while those which lay upon the compact soil of the Jura rocks had 

 escaped. The greater part of Kienberg stands upon a cleft of the 



