Author William Duncan MacMillan (1871-1948) was an American mathematician and astronomer. MacMillan made many noted contributions in mathematics and astronomy. The crater on the Moon, MacMillan, is named to commemorate him.
Wikipedia states - "He was an early proponent of a theory in the context of solving Olber's paradox (1922) that would later be called the"tired-light hypothesis" of cosmology."
Hardcover book is in good used condition. Book has navy blue cloth covered boards with gold lettering on the spine. Book cover has some light edge wear, some corner wear includes bumped corners. Cover is secure, all pages intact, clean and unmarked. Surface staining and marks on the back cover and marks on the front cover, see photos. Book has some foxing inside the front and back cover, some of the front pages have a faint, narrow discoloration in the bottom margin. Name of previous owner with date and name of university is written neatly on the front fly-leaf. Previous owner was Astronomy and Mathematics professor at Lehigh University in Bethlehem, PA.