I CLIMATE AND ASPECTS OF THE EQUATORIAL ZONE 219 



not be difficult to point out localities within the temperate 

 zone of our maps, which exhibit all the chief characteristics of 

 tropical nature to a greater degree than other localities which 

 are, as regards geographical position, tropical. 



Temperature of the Equatorial Zone 



The most characteristic, as it is the most important feature 

 in the physical conditions of the great equatorial zone, 

 is the wonderful uniformity of its temperature, alike 

 throughout the changes of day and night, and from one 

 part of the year to another. As a general rule, the 

 greatest heat of the day does not exceed 90 or 91 Fahr., 

 while it seldom falls during the night below 74 Fahr. It 

 has been found by hourly observations carried on for three 

 years at the meteorological observatory established by the 

 Dutch government at Batavia, that the extreme range of 

 temperature in that period was only 27 Fahr., the maximum 

 being 95 and the minimum 68. But this is, of course, very 

 much beyond the usual daily range of the thermometer, which 

 is, on the average, only a little more than 11 Fahr. ; being 

 12 '6 in September, when it is greatest, and only 8'1 in 

 January, when it is least. 



Batavia, being situated between six and seven degrees 

 south of the equator, may be taken as affording a fair example 

 of the climate of the equatorial zone ; though, being in an 

 island, it is somewhat less extreme than many continental 

 localities. Observations made at Para, which is on the South 

 American Continent, and close to the equator, agree, however, 

 very closely with those at Batavia ; but at the latter place all 

 the observations were made with extreme care and with the 

 best instruments, and are therefore preferred as being 

 thoroughly trustworthy. 1 The accompanying diagram, show- 

 ing by curves the monthly means of the highest and lowest 

 daily temperatures at Batavia and London, is very instructive ; 

 more especially when we consider that the maximum of tem- 

 perature is by no means remarkably different in the two 



1 " Observations made at the Magnetical and Meteorological Observatory 

 at Batavia. Published by order of the Government of Netherlands, India. 

 Vol. I. Meteorological, from Jan. 1866 to Dec. 1868 ; and Magnetical, from 

 July 1867 to June 1870. By Dr. P. A. Bergsma, Batavia, 1871." This 

 fine work is entirely in English. 



