This photograph shows a black and white portrait of Tay Koh Yat. Description by Library staff. Portrait of Tay Koh Yat. This is part of a set of two black and white photographs, the other being his family portrait. Tay Koh Yat (1880-1957) was an entrepreneur, a Chinese community leader and well-known bus operator in Singapore. He started Tay Koh Yat Bus Company in 1938 which later became the largest Chinese bus company.