While our friends were resting in the hotel after their round of sight-seeing, the conversation turned upon caste--that peculiar social and religious institution to which reference has already been made. In response to the inquiries of the boys, Doctor Bronson said the system of caste was not fully understood even by those who had lived for years in India, but it might be described in a general way as a distinction based on birth, and incapable of change. "There are," said the Doctor, "four great castes, and these have numerous subdivisions, which include eighteen principal and more than a hundred subordinate classes. By the rule of caste no man can ascend to a higher or go down to a lower; he may commit murder and other crimes without losing caste, but if he violates any of the rules of ceremony, however slight, he becomes an outcast, and can only be restored on payment of a fine proportioned to his means. For some offences there is no restoration; the outcast, whether temporary or perpetual, is not recognized by his friends or even by his family, and any one who ventured to speak to him or give him the least assistance would be liable to the same fate. "The four classes are, first, the Bramins, who are supposed to have come from the head of the Creator, and to be endowed with attributes of divinity which all below must recognize. Kings and emperors are not exempt from paying reverence to the Bramins, and the poorest of the latter considers himself superior to the Sovereign of England or the Emperor of China. The Bramin is of so exalted a character that he will eat no food that a man of lower caste has touched, and even to allow the shadow of the latter to fall on him would be pollution. In Southern India it was formerly considered quite justifiable for a Bramin to strike dead a low-caste man who had touched him, whether accidentally or otherwise, and in the native states of India at the present time the people of low caste are under heavy disabilities. "The second caste have a sort of sacred character, but far below that of the Bramins; they are the military and executive class, and carry out the laws which the Bramins make. The third caste comprises the mercantile and agricultural classes; and the fourth, or _sudra_, includes all the servile classes, who must remain forever in a state of dependence, and are not allowed to acquire property, or even to be instructed in anything more than the work they have to do. It is forbidden for a Bramin to read the sacred writings to the sudras, or give them any religious instruction whatever. Below the sudras are the _pariahs_, or outcasts; no men of any caste will associate with them, and they are regarded as utterly without any redeeming qualities. A pariah who should come into the presence of a Bramin, under the old rules of caste, would be liable to be put to death.