This volume, written between May 3 and December 2, includes essays on mineralogy, the vegetable kingdom (such as botany and fruitification), and the animal kingdom (such as zoology, ornithology, and generation of animals).

Chiefly correspondence with Alexander John Gaspard Marcet on chemistry, with references to Sir Joseph Banks, Jean Francois Berger, Johan Jakob Berzelius, Jean-Baptiste Biot, and others; a few letters to and from John Bostock, Thomas Cooper, John Wilson Croker, Giovanni Fabbroni, and Henry Penneck.

These are primarily scientific letters from Buckland. The subjects mentioned include Milne-Home's seismological investigations, Wheatstone's self-registering instruments, geology (glacial phenomena in Scotland, mineralogy, etc.), numerous references to fossils, and mentions of Mastodon bones and sloths.