140 EFFECTS OF HEAT. 



A. Because the higher regions of the 

 air are laden with vapour, on the very 

 point of condensation, which the rising 

 sun cannot disperse. Hence our Lord's 

 observation, "In the morning (ye say) 

 it will be foul weather to-day, for the sky 

 is red and lowering." (Matt. xvi. 3.) 



Q. Why is a GREY MORNING an indication 

 of a FINE DAY ? 



A. Because that air alone contiguous 

 to the earth is damp and full of vapour. 

 There are no vapours in the higher 

 regions of the air to reflect red rays ; 

 and hence the morning-light looks grey. 



Q. What difference (in the state of the air) 

 is required, to make a GREY and RED SUNRISE ? 



A. In a grey sunrise, only that 

 portion of air contiguous to the earth is 

 filled with vapour ; all the rest is clear 

 and dry. But in a red sunrise the air 

 in the upper regions is so full of vapour 

 that the rising sun cannot disperse it. 



Q. Why is a GREY SUNSET an indication of 

 WET? 



A. If the air on the surface of the 



earth be very damp at sunset, it is a 



