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situation of the place, which is wholly surrounded by hills of from 400 to 1,400 feet height, except between the points of S.W. and S.S.W.
As is the case in the China sea, we find that in Nagasaki the north monsoon (for here it is more correct to speak of it as a north and not a N.E. monsoon) has more than twice as long a duration as the S.W. wind. September and sometimes the first days of October are the periods at which the S.W. changes to the North monsoon, whilst the change from the N. to the S.W. wind takes place much more gradually during the two month’s of April and May (and sometimes in the last days of March.) East and south-easterly winds are comparatively rare in Nagasaki although it must be said that these winds are the true carriers for these place, as well as for a large part of the east coast of the Japan islands. It is nearly always sure that there will be rain, if E. and S.E. winds prevail for one day or longer. This fact is easily explained. The E. and S. E. winds, which have travelled over the warmer parts of the Pacific Ocean must necessarily get saturated and yield their water when they are cooled by the vegetation on the Japanese coast, in the same manner as is the case with the S.W. wind on the west coast, of Europe.
In regard to the prevailing winds and the height of the barometer, the year may be divided into two monsoon periods, and in order to give a simple review of these periods I have constructed Tables 1 1871 and Tables I. II. III. for 1872. These figures show how many times in each hundred observations the wind has been N. E. and S. W. and so on. The length of the triangle outside the circle gives, by comparison with the scale, the relative number of winds, which have prevailed during each period. If for instance the N wind only should have prevailed in the month of December 1871 (Table I. 1871), the radius N. would have had the length of the whole scale (100). But the N. wind blew only 23. 2 times in each hundred observations, and therefore the length of the radius is 23. 2 parts of the scale. We have placed the numbers expressing
