June till the end of September it is humid and moderately warm.

There has been an observatory for many years past in Manila under
the management of the Jesuits. The following is an epitome of the
yearly meteorological report for 1867, for which I am indebted to
Professor Dove:

Barometrical readings.--The average height of the mercury was, in 1867,
755.5; in 1865, 754.57; and in 1866, 753.37 millimeters.

In 1867 the difference between the highest and lowest barometrical
readings was not more than 13.96 millimetres, and would have been
much less if the mercury had not been much depressed by storms in July
and September. The hourly variations amounted to very few millimeters.

Daily reading of the barometer.--The mercury rises in the early morning
till about 9 a.m., it then falls up to 3 or 4 p.m., from then it rises
again till 9 p.m., and then again falls till towards day-break. Both
the principal atmospheric currents prevalent in Manila exercise
a great influence over the mercury in the barometer; the northern
current causes it to rise (to an average height of 756 millimeters),
the southern causes it to fall (to about 753 millimeters).

Temperature.--The heat increases from January till the end of May,
and then decreases till December. Average yearly temperature, 27.9°
C. The highest temperature ever recorded (on the 15th of April at 3
p.m.) was 37.7° C.; the lowest (on the 14th of December and on the
30th of January at 6 a.m.), 19.4° C. Difference, 18.3° C. [59]

Thermometrical variations.--The differences between the highest