Sutton — Soine Observations of Dew at Kimhcrleij. 



269 



Taking dew and frost together at 11 p.m., we have tlie following monthly 

 summary of the number of times either has appeared iu four years, compared 

 with the mean cloudiness of the sky : — 



Year, 



140 



24 



There is no very obvious relationship between the two columns of tliis 

 Table, saving that the months having the clearest nights are the months of 

 least dew. The moot inference is that conditions not favourable to the 

 formation of dew are also not favourable to the formation of cloud. 



Table II shows the number of times dew (or frost) has been observed in 

 the four years, arranged in columns according to the corresponding state of 

 the sky, and in lines according to the hour. The Table shows that at 8 a.m. 

 the conditions least favourable to the formation of dew occur when the sky is 

 one-half covered with cloud, a completely obscured sky being nearly as 

 favourable as when only 10 per cent, is clouded. There were 161 observations 

 of dew under a clear sky, 61 observations when less than a tenth of the sky 

 was cloudy, and 115 observations when the clouds covered 10 per cent, or 

 more of the sky. At 8 p.m. dew is seldom observed at Kimberley when 

 there is much cloud — no doubt because the clouds somewhat retard the fall of 

 temperature. But that the dew will form, given time enough, under a cloudy 

 sky is proved by the numbers for 11 p.m., showing that dew under an over- 

 cast sky is more common than under any assigned degree of cloudiness 

 exceeding zero. Taking all hours together, we have 258 observations of dew 

 with clear skies, 85 observations with just a little cloud, and 177 observations 

 when the cloud state is conspicuous. Such a result scarcely supports the 

 statements quoted above, and that more especially when it is remembered 



