The mode in which instruction has hitherto been conveyed, on the peculiar subjects of the present work, has chiefly been by small books, in question and answer, denominated catechisms. But such, however respectable in themselves, or however advantageous for children, are wholly insufficient for persons who are in search of extended knowledge, and desirous of furnishing their minds with useful information. On these subjects there has not hitherto been published any work in which they are collectively to be found; nor could a knowledge of them be obtained but by the consultation of many and expensive writings. That they are generally important to be known will not probably be denied. It has consequently been the object of the author to compress all the interesting information that could be obtained respecting them, within as narrow a compass, and at the same time to render this information as entertaining, and as devoid of technical words and phrases, as possible. The scheme of the work will, it is hoped, be found sufficiently simple. The passage in smaller characters at the head of each article, is in general so arranged as to reply to the questions, “What is?” “What are?” or “How do you know?” For instance: “What is flint?” The answer will be found thus: “Flint is a peculiarly hard and compact kind of stone, generally of smoke-grey colour, passing into greyish white, reddish, or brown. It is nearly thrice as heavy as water, and, when broken, will split in every direction, into pieces which have a smooth surface.” The author is aware that, in many instances, the definitions are defective: but this has, in general, arisen from a necessity of rendering them short, and at the same time of using such terms as would be likely to convey information to the minds of persons who have had no previous knowledge of the systems of natural history.