The Outline of Science was written specifically with the man-on-the-street in mind as the target audience. Covering scientific subjects ranging from astronomy to biology to elementary physics in clear, concise and easily understood prose, this popular science work is largely as relevant today as when first published in 1922.

In this second volume (of four), we learn about microscopy, and the intricate workings of the human body and mind. The major part, however, is devoted to the Natural History of birds, mammals, and insects. (Summary adapted from the first volume by Availle.)