A Book of Hours contains 24 essays, one for each hour of the day, that seek to bridge the gap between definitive scientific philosophy and the sheer unadulterated beauty that Donald Culross Peattie envisioned within everyday life. The Boston Transcript referred to this collection as "science, in sheer poetry," and the Chicago Daily Tribune mused that "it leaves one a better man for having read it" and offers "the inevitableness of natural laws and the truth of beauty, if one cares to seek it."