The Tartars, unlike other people, generally prefer the steep side of a hill for the site of their villages, rather than those level situations vulgarly known as "eligible building-lots." By excavating a space out of the hill, in proportion to the accommodation required, the architect is saved the trouble of building a back wall, while he simply fills up with mud the angles at the sides. The roof, which thus, as it were, projects out of the hill, is perfectly flat, and covered with mould. It extends beyond the front walls, and, supported by posts, forms a sort of verandah.
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Sears, Robert. An Illustrated Description of the Russian Empire. New York: Robert Sears, 1855