36 MADEIRA METEOROLOGIC. PART iv. 



its high temperature, and extreme capacity in that state 

 for absorbing watery vapour ; and it is probably never 

 fully saturated, so long as its primitive high temperature 

 is kept up by continued reinforcements of hot wind from 

 the desert. But when that wind has blown itself out, 

 say in three or four days, the temperature at a distance 

 from Africa falls ; and the great quantity of water- vapour 

 brought there into the higher strata of the atmosphere, 

 by the temporary warm current from below and eastward, 

 can hardly do anything else than precipitate itself as rain 

 or dew. Wherefore we find Dr. Mason recounting, on 

 his p. 48, in these words : 



" I may also state that rain generally falls within 

 twenty-four hours after the Leste has altogether ceased ; 

 and that I have seen a very strong precipitation of dew 

 three hours afterwards, the atmosphere being reduced 

 from 1 7 to 7 of dryness on my hygrometer; and at seven 

 o'clock the following morning to 2 ; while the plants and 

 shrubs were covered with dew." 



But from our low, almost sea-side, station at Quinta 

 de Corvalho, where we felt neither the heat, nor the 

 dryness, nor the force of a true Madeiran Leste, we 

 observed as follows on June 26, 1881; the account being 

 extracted from my observing ledger, in which it was 

 entered the next day : 



