Meteorological Thermometer

Listing ID #3173024

Sunshine recorder consists of a glass sphere mounted concentrically in a section of spherical bowl, the diameter of which is such that when the instrument is exposed to the sun's rays, they are focused sharply on a card held in grooves in the bowl. Three overlapping pairs of grooves are provided in the bowl cards suitable for different seasons of the year. The sharply focused sun's rays burn a trace on the card which has a time scale printed on it. The length of the burn indicates the period of bright sunshine during the day.
Specifications :

• Material 
  
  • Base - Good quality marble or similar stone, black or white
  • Sphere - Uniform and well annealed glass
  • Bowl - Tin bronze
  • Pivot - Brass 9.2.2 Dimensions  The instrument shall have the dimensions indicated in figures 9.1 and 9.2.

Sunshine cards  Properties and dimensions of sunshine cards are given in Appendix A of IS - 7243-1974.