Injury from Cold During Growing Period. 133 



Example : Dry-bulb reading 47° 



Wet-bulb reading .40° 



Wet-bulb depression 7° 



Table for Computing the Dew Point in Degrees 

 Fahrenheit. 



Dby 

 Bulb. Wet-Bulb Depression. 



Opposite 47°, in the left hand column, and under 7 

 in the top line, we find 28°— the dew point. If these 

 readings are obtained toward sunset on a clear, still 

 evening, we should expect frost, because the dew point 



