68 H. DEANE. 



And the extent of the drought is directly proportional to the area, 

 the intensity of any drought being the particular area divided by 

 the length. It is proportional to the mean depth of area coloured 

 brown. The peculiarity of the different years is well shown in 

 the diagrams (Plate 3). 



(Added July 31). 

 I would recommend that as in any district many differences in* 

 soil and situation occur, some standard might be adopted for 

 purposes of recording observations. If the evaporation from this 

 standard soil under different conditions could be determined once 

 for all, the observer would only have to note the temperature and 

 hygrometric conditions as they occur each day and plot the corres- 

 ponding rates of evaporation on the diagrams. The gauging of 

 the differences in drought effects through any variation of soil 

 and surroundings could then be left to the individual judgment. 

 A decision as to what should be taken as standard soil and con- 

 ditions is in the first place necessary, after which an exhaustive 

 system of experiments should be made as to daily drying under 

 varying conditions of temperature, dryness of air, wind, etc. 



