The Hokusai Manga (北斎漫画, "Hokusai's Sketches") is a collection of sketches of various subjects by the Japanese artist Hokusai. Subjects of the sketches include landscapes, flora and fauna, everyday life and the supernatural. The word manga in the title does not refer to the contemporary story-telling manga, as the sketches in the work are not connected to each other. Block-printed in three colours (black, gray and pale flesh), the Manga comprise literally thousands of images in 15 volumes, the first published in 1814, when the artist was 55. The final three volumes were published posthumously, two of them assembled by their publisher from previously unpublished material. The final volume was made up of previously published works, some not even by Hokusai, and is not considered authentic by art historians.