A 200-year-old Chinese mansion in Bangkok’s heart is not an obvious place for a scuba school, but in a city relentlessly demolishing its architectural heritage the business is helping preserve the historic home. Diving instructor Poosak Posayachinda’s family has owned the traditional teak-walled So Heng Tai mansion for eight generations, but it lives on thanks largely because he converted it into a scuba academy. The survival of the building, originally built as a home and office for a family business trading birds’ nests with China, is a rare success story in a city that harbors little ...