Abbot-type silver disk pyrheliometer
Date: 1910-1920
Inventory Number: 1996-1-0383
Classification: Pyrheliometer
Dimensions:62 × 41.5 × 27.5 cm (24 7/16 × 16 5/16 × 10 13/16 in.)
Description:
A brass tube 1.75" od, 12.5" long mounted on a cylindrical wooden chamber held in an equatorial mount on flat tripod foot with cross piece on one of them. The instrument is portable, and is built around an insulated mercury bulb thermometer, -10 degrees C to 50 degrees C, whose reservoir is encased in a blackened silver disk set inside the wooden cylindrical chamber at the bottom of the instrument. Its stem is encased in a silver cylindrical rod at the side of the main chamber. The level of the thermometer mercury column is read visually.