DURING RAIN OR SNOW. 243 



From column (6) it appears that during hours of rain, winds be- 

 tween N.N.E. through east to S.S.W., with an interruption at south* 

 have a relative duration above the average relative duration of ail winds* 

 and winds from north through west to S.W. have a duration below the 

 same average. The wind that most frequently occurs during hou'S of 

 rain is from E.N.E. ; and the N.W. wind is that which is most rarely 

 accompanied by rain. 



For the heavier rains we see from column (7) that the winds whose 

 duration is above the average are limited to the four points N.N.E. to 

 East. The range is also greatly increased, the E.N.E. wind being 18 

 times as frequent as the N.W. wind ; whereas when lighter rains are 

 included, the E.N.E. wind is less than 6 times as frequent as the N.W, 

 lyind. 



The increase of the ranges in Table 11. as compared with those in 

 Table I. is explained by the circumstance that westerly and north* 

 westerly winds, though blowing seldom during the actual fall of the 

 rain, frequently occur during some part of the days in which rain falls, 

 particularly after the rain has ceased, and thus tend to conceal or 

 diminish the predominance of the E.N.E. winds that is so conspicuous 

 in Table II. 



The distribution of the winds throughout days of snow is exhibited 

 in Table III. 



With the view of examining whether the distribution of the winds 

 is ajBFected by the magnitude of the snow storm, the method employed 

 m computing Table I. has been applied in Table III. to the following 

 four classes, whereof each class is taken so as to include all the higher 

 classes : 



Class I. includes every instance in which snow was recorded. 



Class II. is limited to those cases wherein the snow in twenty-four 

 hours was equal to or exceeded one inch. 



Class III. is limited to falls of three inches and upwards. 



Class IV. is limited to falls of six inches and upwards. 



From column (6) it appears, when light falls and the heaviest snow 

 storms are ranked together indiscriminately, that 291 hours in 1000 

 hours of N.E. winds, 330 hours in 1000 of west winds, and 86 hours 

 in 1000 of south winds are included in days of snow. Also, from col- 

 umn (10), the winds whose duration during days of snow are above 

 the average for all winds, lie between N.E. through north and west to 



