Charles Frederick Chandler (December 6, 1836 - August 25, 1925) was an American chemist, best known for his regulatory work in public health, sanitation, and consumer safety in NYC, as well as his work in chemical education at Columbia University. He implemented major reforms to improve infant nutrition, including stopping the sale of watered-down milk, and instituted a corps of traveling physicians to tend to the residents of tenements. He was a strong advocate for tenement reform, designing tenement houses that were cleaner and brighter than those most prevalent in the City, and pushing a Tenement House Act through legislature. John O'Neil, circa 1870-80 (cropped and cleaned).