What are ducks the item of clothing Maugham refers to?

In W. Somerset Maugham's works, particularly in "The Moon and Sixpence," the term "ducks" refers to a type of lightweight cotton fabric often used for making clothing, especially in warm climates. It is a durable material that can be used for various garments, including shirts and trousers. Maugham's use of the term reflects his keen observation of clothing styles and societal norms in the settings he describes.