77
the per-centage of wind directions inside the circle of the diagram.
It can immediately be seen from these diagrams that northerly winds have prevailed during the months of November and December, 71.
The wind-rose on Table I. 1872, shew the direction and percentage of winds (a.) over the whole year, 1872, (b.) over the changing months April, May and September, (c.) over the time of the S.W. monsoon in June, July and August, and (d.) over the period of the N. monsoon, October, November December, January, February and March.
The first diagram shows that N., S.W., N.E., N.W. winds are the most prevailing during the whole year, whilst S., S.S.E., S.E., and E. are much more rare.
The following diagram shows how in the changing months April, May and September, the direction of wind is very variable and that N. and N.E. winds have still during these months a preponderance over the S.W. wind. The wind diagram c. shows clearly how the S.W. monsoon prevails in June, July and August, whilst diagram d. explains the N. monsoon.
Table II. contains diagrams made up from 1,000 observations formerly made at Desima, during a period of 15 years. Although they agree in the main with our diagrams over the same months of the year, 1872, they differ slightly in some subordinate points.
They are however not very important, because the diagrams agree in the main points.
Table III. 1872, contains the diagrams for each month of the year 1872, and can easily be understood after the explanations we have already given.
Table V shows that the highest barometer prevails in the coldest months January and February when the atmosphere has its maximum density, whilst the lowest barometer occurs in August, during the prevalence of the S.W. monsoon.
It is however a very remarkable fact, not easily to be explained, that during June, July and August at the
