ME. H. F. BLANFOED ON THE WINDS OF NOETHEEN INDIA. 
567 
May to October winds from between north-east and south-east contribute from 70 to 80 
per cent, of the observations. The annual change is rather one of oscillation than 
rotation. From February to August there appears to be a gradual veering of the mean 
direction from north by west, through north, north-east, and east to east-south-east ; and 
the change from the summer to the winter monsoon is retrograde, and consists in a 
gradual strengthening of the northerly current till the latter attains its extreme direc- 
tion from north by west in January. 
At Mooltan the wind-system is again different. Here south-west is the predominant 
quarter, to the extent of 29 per cent, on the average of the year; north-west stands 
next in importance, and due east and west winds amount to only 2 and 3 per cent, 
respectively. It is possible that the low proportion of west winds may be due to some 
local obstacle, influencing the currents that act on the wind-vane and diverting them 
either to north or south of their primitive direction. But even if we admit that a por- 
tion of the north-west and south-west winds are possibly diverted west winds, the fact 
remains, that at this station winds from the southerly quarters are equally numerous 
with those from northern directions, which is not the case at any other of the Punjab 
stations here noticed. The predominance of westerly over easterly winds, on the other 
hand, is a condition which also obtains at Rawul Pindee and Lahore, though not at 
Hera Ishmail Khan. With respect to the annual change of mean direction, the Table 
shows considerable irregularities, which may be due in part to the cause above suggested, 
and in part to the inequality of the periods from which the data for the several months 
have been obtained. In January the resultant appears to be decidedly north-north- 
west; in February and March less decidedly north by east and north by west; and the 
wind then appears to back through north-west and west to south-west by south, which 
is its prevailing mean direction during the summer monsoon, and is most decided in 
September. In the latter months of the year the direction of the change seems to be 
reversed, and the winds veer normally and somewhat abruptly through west to north 
and north by east, which is the mean direction in December. 
The wind-system of Lahore resembles to a certain extent that of Rawul Pindee, 
except that, owing to the more exposed position of the station, the prevalent currents 
are less exclusively east and west. The most frequent wind is from north-west (25 per 
cent.), and north-east is second in importance (18 per cent.). South winds are rare, 
and do not exceed 2 per cent, on the average of the year ; and those from the three 
southerly points are only 22 per cent, against 52 from the opposite directions. As at 
Rawul Pindee and Mooltan, westerly winds preponderate over easterly, but to a less 
extent, the proportions being 50 to 39. ; The prevalent mean direction from October to 
April is north-west and north-north-west ; but north-east winds on the one hand, and 
west winds on the other, form a not inconsiderable proportion of the whole. From 
March onward, east and south-east winds become more frequent, and in July and August 
preponderate. They are not, however, very steady, and north-east and south-west winds 
are nearly as common as those from south-east. In September westerly winds regain 
