Abstract: A new system developed for calibrating the horizontal incidence pyrheliometer is described. The pyrheliometers to be calibrated are exposed simultaneously with a standard pyrheliometer in an integrating sphere. Calibrations ...

Abstract: The following devices for simplifying the operation of the Abbot Silver Disk Pyrheliometer are described: (1) an automatic shutter, (2) a simplified heating and cooling timing sequence and (3) an improved method of reading ...

Abstract: A recording infrared absorption hygrometer which measures the absolute humidity in a 1-meter light path is described. Record is obtained on a remote self-balancing potentiometer. Use is made of the 1.37 µ water vapor ...