1 DECEMBER 1838, Page 18

A Catechism on Heat, by Hucio Rain. This is a

very valuable little publication, containing in a small compass the cream of the subject at a very trifling price. The principles, and most striking facts connected with heat, are clearly unfolded, in a style which is commensurate with the subject, without ever becoming strained or stilted. In establishing the truth of the laws laid down, a variety of simple experiments are instanced, which, not only carry conviction to the mind at once, but in many cues will furnish the reader with an easy and entertaining mode of testing them himself. The different instruments for discovering the pre- sence and properties of heat, as the thermometer, are also de. scribed, with the reasons why they effect their object. Mr. Rain's Catechism on Heat is one of the best of the innumerable little books of this kind we have seen.