Europe : — a popular Physical Sketch. 15 



Annual. Winter. Summer. 



Lisbon, ... 38° 30' N. L. 61.2° 52.9° 71° 



Madrid, ... 40° 30' 58.3° 43° 76.7° 



Considering Madrid is situated nearly two degrees more 

 northerly, and 2133 feet above Lisbon, the mean tempera- 

 ture is proportionally higher in Madrid, which is to be 

 ascribed to the heating of the extensive table land; the 

 winter, however, is 10.1° colder, and the summer 4.6° warmer, 

 by which a continental climate is produced on the table land. 

 In Madrid the thermometer has been observed to rise as 

 high as 10.40°, and to fall as low as 16.3°, or perhaps lower. 

 In Lisbon, on the contrary, the highest point of the mercury 

 has been 69°, and the lowest 27.5°. Snow and frost are 

 phenomena of rare occurrence in Lisbon, but not at all 

 uncommon in Madrid. Sufficient observations to determine 

 the temperature of the south coast of Spain do not exist ; 

 in all probability the mean temperature will be found amount- 

 ing to 65.7°, perhaps a little more ; the winter is very mild. 

 At Faro (Algravia) the lowest point at which the thermome- 

 ter was observed is said to be 45.5°. 



The annual quantity of rain amounts to twenty-six inches, 

 in Madrid to nine and a half inches, the table land conse- 

 quently suffers much from drought, and in this respect also 

 presents a contrast with the coast. On the table land, 

 as well as on the coasts, the summer rain is very scanty, 

 but the autumn and winter are the regular rainy seasons ; 

 thus, in Lisbon one twenty-fifth part only of the annual 

 quantity of rain falls during summer ; but during winter 

 more than one-third. In Estremadura it is said, that seven to 

 nine months sometimes pass without any rain. On the table 

 land the atmosphere is almost uninterruptedly clear during 

 the summer. 



Perpetual snow occurs on Serra Nevada only (from which 

 its name) but the table lands of Serra Guadaramo and Estrella 

 are covered with snow for four or five winter months, they 



