Originally published in 1829, this book is a comprehensive guide to the use and calibration of barometers and thermometers. The author, Jeffery Dennis, was a respected instrument maker and meteorologist, and his technical expertise and attention to detail are evident throughout the text. The book includes detailed descriptions of the various types of barometers and thermometers, as well as instructions for using and adjusting them for optimum accuracy. This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.