But, again, there are immunities more complete than that of the Negro, from marsh affections; and, further, these immunities may be lost, either in the case of an entire group of population, or in that of isolated individuals. I will here borrow two striking examples from M. Boudin’s work.
Elephantiasis, that affection by which certain parts of the body are sometimes deformed in so strange a manner, is found in the Indies and at Barbadoes. In the latter island, Negroes alone were attacked by this hideous disease till the year 1704. One White was, in that year, affected by it for the first time. But the disease made way, and in 1760 it had extended to the creole population. Whites of European origin have, as yet, escaped.
The elephantiasis of India is found in Ceylon. There, again, it only attacks natives, creoles and individuals of mixed blood. Hindoos and Europeans, strangers in the island, are exempt from it. Scott, quoted by M. Boudin, states that only one case of this disease had been observed in a European White. But this individual had inhabited the island for thirty years; acclimatisation had been earned so far in his case as to cause him to lose his ethnological immunity.
On the other hand, we have seen, in speaking of acclimatisation, that creoles easily live and prosper in certain localities which are most dangerous to immigrants. They have, therefore, acquired, at the price of sacrifices made by preceding generations, a relative immunity which is not enjoyed by the majority of Europeans.
In the acquisition of one of these immunities, a race may lose another. In connection with the cholera which I have just mentioned, creole Whites and Negroes were attacked to an appreciably greater extent than Whites and Negroes who had recently immigrated, and were consequently not yet acclimatised. Thus, the conditions of life in Guadaloupe, and those of other Mexican islands, seem to exercise a double action. On the one hand, it diminishes in a considerable degree the aptitude to contract yellow fever; on the other, it renders the human organism appreciably more accessible to the influence of cholera.
VI. Such significant facts as these require no comment. It is clear that we have here those relative immunities which several polygenists wished to consider as specific characters. Without possessing anything approaching the importance which, from this point of view, is possessed by physiological phenomena, they equally render evident the fundamentally identical nature of all human groups. Owing their special element essentially to acquired nature, they demonstrate the difference of races rather more clearly than physiological phenomena. Both, however, are equally functional; and the functions acting necessarily under the immediate influence of the conditions of life, demonstrate almost in the same degree the preponderating influence of the latter.
VII. We cannot touch upon questions of ethnological pathology without saying a few words upon the strange and fatal influence which the White race seems to exercise upon certain inferior races whose territories it has invaded.
Nowhere is this melancholy phenomena more striking than in Polynesia. Figures here speak with touching eloquence.
In the Sandwich Islands Cook calculated the population at 300,000. In 1861 there were but 67,084, about 22 per cent. of the original population.
In New Zealand Cook found 400,000 Maories. In 1858 there were only 56,049 remaining, 14 per cent. of the former population. Depopulation has continued from that time. From 1855 to 1864 the loss was 22 per cent. for the province of Rotorua, the Lakes and Maketou; it was 19 per cent. in two years, from 1859 to 1861, in the Chatham Islands.