For two centuries the barometer has been an indispensable laboratory instrument. Yet, despite its revolutionary influence on science, W. E. Knowles Middleton here offers the first complete history of the barometer as a scientific tool.

Middleton relies on research from Western European documents and manuscripts of the seventeenth and eighteenth centuries. He begins his story with a pre-history of the barometer, the Torricellian experiment, the subsequent experiments and controversies in the 1640s, and the barometric experiments during the remainder of the century.

Later chapters are concerned with the mercury barometer as a scientific instrument, discussing the efforts to expand the scale to render the instrument portable, and to attain greater accuracy. These chapters follow accounts of mercury barographs, the history of the corrections to the barometer, the history of the mercury barometer in North America, and the luminescence that appears when a barometer is moved in the dark. The final chapters discuss barometers other than those using the weight of a column of mercury.

A large number of the more interesting barometers seen by the author in his extensive travels appears in the appendix. Nearly 200 figures and diagrams depict the wide variety of barometers studied by the author over his long career at the Smithsonian Institution.

W. E. Knowles Middleton (1902–88) wrote 15 books and 75 to 100 scientific papers related to the science of weather instruments and meteorological optics as well as their history. His major contribution was the book Meteorological Instruments, first published in 1953. From 1929–46, he worked for the Meteorological Service of Canada, specializing in measurement and instrumentation. After retiring, he was a professor emeritus and honorary lecturer associated with the Department of History of Medicine and Science at the University of British Columbia.