MR. GLAISHER ON THE RADIATION OF HEAT, AT NIGHT, FROM THE EARTH, ETC. 
[ To/acc page 142.] 
Excess of the reading of a thermometer placed in air at the height of 4 feet, protected from the effects of radiation, above the readings of thermometers placed on different substances fully exposed to the sky, arranged according to the difference of the readimrs of 
the one on Long Grass and that in Air, from observations taken between 1844 January 1 and 1844 May. S 
Feb. 21. 11" O'" ; a thin rail 
falling. Feb. 16, 3 h 0 m ; the sun is shining brightly. Feb. 22, 18 h 45 m ; the sun is high and shining. Feb. 20, 9 h 10 m ; the larger stars are visible only. 
143 
