The second side of the poster has been cropped into three parts for ease of reading. These particular instruments were manufactured by the E. Vernon Hill Company based in Chicago.
Psychrometers, also known as wet-and-dry-bulb thermometers, are a type of hygrometer. They measure humidity by comparing the temperatures of two thermometers, one wet and one dry.
|Original file type||TIFF|
|View in library catalog|