40 EXCURSIONS IN MADEIRA 



night, are evidently referable to the causes detailed in the memoir 

 of Sir Humphry Davy. From the unequal degree and depth of 

 the cooling of the earth and sea, when losing caloric by radiation 

 after the setting of the sun, the surface of the sea, and, consequently, 

 the air wliich reposes on the sea during the night, becomes 

 warmer than the earth, and the air immediately upon it ; both 

 these airs, from the nature of the climate, and the locahty of 

 Madeira, are always nearly saturated with humidity, and the fogs 

 or mists which arise from their mixture are unusually considerable, 

 from the depth of the sea and great elevation of the land : the 

 descending current of colder air mixes with the mist as it forms 

 on the surface of the water, whose comparative warmth keeps up 

 the ascent of the vapours, which thus continue to rise until after 

 the appearance of the sun ; they cover the volcanic peaks behind 

 Funchal, and at a later hour arrive at those of the other parts of 

 the interior, which they abandon after the setting of the sun for 

 the warmer surface of the ocean. In a country where there is no 

 rain for six months together, these regular mists conspire with the 

 torrents to fertilize whole tracts of land, which would otherwise 

 remain useless. 



I started the next morning from Mr. Veitch's Quinta, which is 

 about a mile below the view of the Coural das Freiras, to descend 

 into this beautiful valley on my way to the Pico Ruivo. The 

 road winds for nearly three miles, on the verge of the precipices, 

 before it reaches the point of descent ; and a succession of romantic 

 openings, of varied character, left me loth and unable to decide 

 which was the most sublime. I found the arnica montana, at a 

 height of 3500 feet, and it is said to grow even on Pico Ruivo : the 

 ec Ilium giganteum, not only the most beautiful of its family, but 

 in itself a magnificent tree, starts from the clefts of the rocks, 

 and enhvens the rugged soil with its large bunches of blue flowers, 

 and downy leaves. The rocks presented the same alternations 



