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months of November, December, and January, 

 taking each day the maximum and minimum of 

 the temperature, the heights were 20*2°; 201° ; 

 20*2°. Now from the knowledge we have ac- 

 quired of the distribution of heat in the differ- 

 ent seasons, and at different elevations above 

 the level of the sea, I can deduce within a cer- 

 tain approximation, from the means of a few 

 months, that of the whole year ; almost in the 

 same manner as we determine the meridian alti- 

 tude of a star, by elevations measured out of the 

 meridian. The following are the considerations 

 on which are founded the results I adopt. At 

 Santa Fe de Bogota, the month of January, ac- 

 cording to Mr. Caldas, differs from the mean 

 of the year only 0*2°. At Mexico, very near the 

 temperate zone, the difference reaches a max- 

 imum of 3°. At La Guayra, near Caraccas, 

 the coldest month differs from the annual mean 

 4*9° ; but if the air of La Guayra (and that of 

 Catia) rises sometimes in winter by the Quebra- 

 da de Tipe to the high valley of Caraccas, this 

 valley does not less receive, during a great part 

 of the year, the winds of the east and south- 

 east coming from Caurimare and the inland 

 country. We have learned by direct observa- 

 tions, that at La Guayra and Caraccas the 

 coldest months are 23 2°, and 20-1°. These dif- 

 ferences express a decrement of heat, which, in 

 the valley of Caraccas, is the simultaneous effect 



