It is, however, clear, that many perished by that strange disease, so often fatal to the soldiers and peasants of Switzerland, who die in foreign lands from regret of their native country. They were within sight of Tasmania, and as they beheld its not distant but forbidden shore, they were often deeply melancholy: to this point the testimony of Mr. Robinson is decisive, though not solitary.[25] They suffered much from mental irritation: when taken with disease, they often refused sustenance, and died in delirium. The wife, or the husband in perfect health, when bereaved, would immediately sicken, and rapidly pine away.[26] Count Strzelecki has propounded a curious notion of the laws of extinction, in reference to this race. He states that the mother of a half-caste can never produce a black child, and thus the race dies. His statement would need the most positive and uniform testimony; but it may be added to the curiosities of literature. The decrease of population among the inferior race, when harassed or licentious, is certain; but surely there is nothing occult in this, or requiring further explanation than is afforded by human cruelty and vice. Among those who survive, is the wife of the native Walter George Arthur, the half-caste daughter of Sarah an aboriginal woman. [Looking lately at a picture of Don Quixote, she pointed him out as the man who fought with the windmill.] Her mother has a younger son, now or lately at the Queen's School, and of pure aboriginal blood. A natural law, by which the extinction of a race is predicted, will not admit of such serious deviations.