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I CLIMATE AND ASPECTS OF THE EQUATORIAL ZONE 219not be difficult to point out localities within the temperatezone of our maps, which exhibit all the chief characteristics oftropical nature to a greater degree than other localities whichare, as regards geographical position, tropical.Temperature of the Equatorial ZoneThe most characteristic, as it is the most important featurein the physical conditions of the great equatorial zone,is the wonderful uniformity of its temperature, alikethroughout the changes of day and night, and from onepart of the year to another. As a general rule, thegreatest heat of the day does not exceed 90 or 91 Fahr.,while it seldom falls during the night below 74 Fahr. Ithas been found by hourly observations carried on for threeyears at the meteorological observatory established by theDutch government at Batavia, that the extreme range oftemperature in that period was only 27 Fahr., the maximumbeing 95 and the minimum 68. But this is, of course, verymuch beyond the usual daily range of the thermometer, whichis, on the average, only a little more than 11 Fahr. ; being12 '6 in September, when it is greatest, and only 8'1 inJanuary, when it is least.Batavia, being situated between six and seven degreessouth of the equator, may be taken as affording a fair exampleof the climate of the equatorial zone ; though, being in anisland, it is somewhat less extreme than many continentallocalities. Observations made at Para, which is on the SouthAmerican Continent, and close to the equator, agree, however,very closely with those at Batavia but at the latter ;place allthe observations were made with extreme care and with thebest instruments, and are therefore preferred as beingthoroughly trustworthy. 1 The accompanying diagram, showingby curves the monthly means of the highest and lowestdaily temperatures at Batavia and London, is very instructive ;more especially when we consider that the maximum of temperatureis by no means remarkably different in the two1 " Observations made at the Magnetical and Meteorological Observatoryat Batavia. Published by order of the Government of Netherlands, India.Vol. I. Meteorological, from Jan. 1866 to Dec. 1868 and; Magnetical, fromJuly 1867 to June 1870. By Dr. P. A. Bergsma, Batavia, 1871." Thisfine work is entirely in English.