Note 1 — Chapter XXI
Reading edition
It is remarkable how the same disease is modified in different climates. At the little island of St. Helena, the introduction of scarlet fever is dreaded as a plague. In some countries, foreigners and natives are as differently affected by certain contagious disorders, as if they had been different animals; of which fact some instances have occurred in Chile; and, according to Humboldt, in Mexico. (Polit. Essay on Kingdom of New Spain, vol. iv.)