234 



POPULAR SCIENCE MONTHLY. 



11,500 Feet. Summit of Volcano Irazu. 



7,000 Feet. On the Sierra Candelaria. 



5,000 Feet. A Street in San Rafael. 



3,800 Feet. A Storm on the Volcano Irazu. 



2,500 Feet. Rio Brazil. 



Sea Level. A Public Garden in Port Limon. 



Jose is 67.5°; that of the sea coast is 78.0°. These figures show an 

 average decrease of temperature of 2.8° for every 1,000 feet of altitude. 

 Observations made in other Central American cities, though less re- 

 liable, give even higher figures. On the Mexican tropical plateau, 

 the average decrease of temperature resulting of the ascent is only 2.3° 



