312 Journal of the Asiatic Society of Bengal. [Aug.-Sept., 1913.] 
dryer than usual; the difference in constitution and character 
between the lower and upper currents will be more pronounced ; 
and the nor’wester will be more definite in cloud outline and 
more nearly approaching the type described above. On the 
other hand, if the upper current be weak, thereby indicating 
little opposition to the approach of the monsoon, then the 
clouds will be loose in texture and the transverse motion small. 
That this may possibly prove correct is shown by the fact that 
the nor’westers of the present year differed strikingly from the 
described type, the approach of the first cloud bank being 
anteceded by a smooth very high layer of grey cloud. On the 
other hand some few years ago when the monsoon was by no 
means plentiful almost every nor’wester was of the described 
i. 
(Investigations for which more than one observer is needed). 
(2) Length of path of individual storm. 
(6) Length of storm face. 
(c) Distribution of simultaneous nor’ westers and the dis- 
etween them. 
(d) Velocity of storm travel. 
(e) Variation of rainfall at different points of its path. 
(/) Phenomena at commencement of formation of a nor’- 
wester and during its gradual dispersion. 
I. 
(Investigations which can be conducted by isolated observers). 
(a) Structure of each nor’wester and variation of struc- 
ture during the year. 
(6) Variation of structure from year to year. 
(c) Correlation between the type-structure of the year and 
the date of arrival and the rainfall of the monsoon. 
lai at ee 
