THE METEOROLOGY OF GLEN NEVIS 



653 



the rainfall was more than three times greater. Five cases of this phenomenon have 

 been investigated, the days being 27th and 28th October, 30th December, and 8th and 

 19th January 1902. The rainfall on these days was as follows at the three stations : — 





Ben Nevis. 



Fort-William. 



Aehariacli. 



1901. 

 October 28 



29 . . 

 December 30 



1902. 

 January 8 

 19 



Total . 



Inches. 

 1-53 

 2-29 

 351 



2-05 

 3-56 



Inches. 

 0-63 

 1-70 

 2-62 



0-87 

 2-57 



Inches. 

 0-47 

 1-15 



1-74 



0-47 

 1-99 



12-94 



8-39 



5-82 



In this type of weather the ratio of the rainfall at the three stations, as compared 

 with the normal ratio, is as follows : — 





Ben Nevis. 



Fort-William. 



Achariach. 



Rainy Fohn . 

 Normal 



100 

 100 



. 65 

 42 



45 

 46 



Hence at Achariach the relation between the summit and the base is normal, while 

 at Fort- William the amount is relatively large. This comes out very clearly if we 

 take the Fort- William rainfall as the unit : — 





Fort- William. 



Achariach. 



Ben Nevis. 



Rainy Fohn . 

 Normal 



100 

 100 



69 

 111 



154 

 236 



During the type of weather we are dealing with, the percentage frequency of wind 

 on Ben Nevis was as follows : — 



N. 



N.E. 



E. 



S.E. 



s. 



s.w. 



W. 



N.W. 



Calm. 



3 



1 







7 



6 



43 



32 



8 







Hence the winds on Ben Nevis were almost wholly from the south-west and west, 



which, as shown from the daily weather maps, also prevailed over the district generally. 



Table VI. shows the mean values at the three places, the hourly departures from 



TKANS. ROY. SOC. EDIN. — VOL. XLIV. 



4 O 



