472 



BEN NEVIS OBSERVATORY. 



[1897. 



ANEMOMETER. 



Miles per hour. 



The following tables give the readings of the Robinson Hemispherical Cup Anemometer 

 at Ben Nevis Observatory for such times as it was working. The anemometer is mounted 

 on the roof of the tower of the Observatory and stands 5 feet above the roof of the tower, 18 

 feet above the flat roof of the main part of the Observatory, and about 32 feet above the 

 ground. It has 4 cups, 5 inches in diameter, mounted on arms measuring 15 inches from 

 centre of spindle to centre of cup, and its records are reduced to miles per hour by the factor 

 2-841. 



The anemometer can be used only when the temperature is above the freezing point, 

 or on the rare occasions when it passes below the freezing point with a dry atmosphere. 

 The presence of fog or mist when the temperature is below 32° at once chokes the 

 mechanism with ice, and either stops it, or so retards its motion, as to render the readings 

 misleading. The tables printed here contain all the satisfactory records from 1893 to 1897 

 inclusive. During 1893 and 1894 the anemometer was in the maker's hands for repairs and 

 alterations. On 15th May 1896 the flexible shaft broke and the instrument was out of use 

 till the 28th of July. The other breaks in the record are due to frost. 



Each month in which any record was got is printed separately. At the right hand 

 side is given, 1st, the mean value of all days on which records were got for the whole 24 

 hours, and 2nd, the maximum hourly value of every day whether complete or not. On 

 incomplete days no mean is given, and the maximum refers only to the time the anemometer 

 was working. The highest maximum value for each month is put in bold faced type. At 

 the foot of each month are the mean values for each hour ; in computing these, only the 

 entries on complete days are taken. 



ANEMOMETER. 



Miles per hour. 



JUNE 1895. 





1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



11 



12 



13 



14 



15 



16 



17 



18 



19 



20 



21 



22 



23 



Mid- 

 night, 



Mean. 



Max. 



1 



2 

 3 

 4 

 5 



6 

 7 

 8 

 9 

 10 



11 



12 

 13 

 14 



15 



16 

 17 



18 

 19 



20 



21 

 22 

 23 

 24 

 25 



26 

 27 

 28 

 29 

 30 



Mean 



8 

 3 

 1 









 11 

 25 



9 



9 

 11 



14 



20 



14 

 9 

 6 



17 



12 



1 

 5 

 6 



8-9 



2 

 2 

 



2 



2 

 10 

 21 



1 



10 



5 



15 

 19 

 20 



20 

 9 



16 



10 

 4 

 5 



8 



9-2 



2 

 7 

 



3 



5 

 13 



18 

 7 



9 

 9 



13 



9 



22 

 18 



9 



17 



12 



6 



8 



9 



9-7 



3 



4 



1 



4 

 6 



15 



21 



8 



8 



12 



15 

 16 

 29 

 20 



8 



18 

 12 



7 

 3 

 8 



11-0 



5 

 6 



7 



5 



7 



14 

 18 



6 



7 



12 



■» 



11 

 17 

 23 



19 

 8 



21 



11 



8 



2 



8 



10-9 



5 

 6 

 3 



6 



4 

 10 

 20 



5 



5 



9 



15 

 12 



26 

 12 



7 



22 

 8 



10 

 2 

 9 



10-1 



6 

 6 

 2 



7 





 10 

 20 



9 



4 



8 



14 

 11 

 32 

 10 

 9 



18 

 6 

 9 



5 

 9 



10-2 



5 

 6 



1 



3 

 



10 

 9 



8 



3 



11 



12 

 17 

 34 

 10 



7 



17 

 1 



11 

 6 



10 



9-3 



4 

 2 

 3 





 

 15 

 6 

 9 



2 



12 



11 

 13 



27 



7 

 2 



17 

 3 



12 

 6 

 6 



7-9 



5 

 4 

 1 





 3 



18 



10 



9 



4 



7 



10 



15 



17 



1 







19 

 4 

 9 

 6 

 6 



7-6 



1 



4 

 1 







2 

 18 

 10 

 10 



5 



9 



10 



18 



8 







1 



15 



6 



8 

 6 



7 



7-1 



1 

 3 



1 



2 



2 



16 



8 



14 



3 







8 



13 



20 

 4 



1 

 4 



12 



5 



8 



8 



10 



7-3 



2 

 

 4 

 2 



4 



2 

 14 



9 

 13 



3 



1 

 9 



13 



18 







3 



5 



13 



5 



11 



7 

 11 



7-4 



4 

 

 2 



1 



4 



2 

 25 

 12 

 12 







2 

 9 



15 



19 







4 



7 



14 

 7 



10 

 12 

 10 



8-7 



i 



11 





 



2 



2 



2 

 22 



9 

 12 



2 



o 

 11 



4 



13 

 14 



1 

 3 



7 



14 

 8 



10 

 9 



11 



77 



12 

 5 



1 

 1 







1 

 23 



9 

 12 



3 



3 



7 

 4 



4 



10 

 14 



1 



1 



8 



12 



7 



4 



7 



10 



7-0 



15 

 5 

 1 

 









 18 

 10 

 11 



5 



2 



3 

 1 



6 



12 



15 



2 



1 



11 



11 

 5 



10 

 9 

 6 



7-1 



8 

 6 

 1 



2 







2 

 14 

 12 

 13 



7 



4 

 3 



8 



12 



16 

 2 

 2 



12 



11 

 7 

 5 

 9 

 5 



7-3 



8 

 9 



8 

 4 







2 

 22 



6 

 13 



3 



2 



5 



11 

 13 



3 



1 

 13 



8 

 4 

 2 

 6 

 5 



7-2 



12 

 11 



4 

 1 







5 

 24 



6 

 13 



5 

 1 



5 



13 



11 

 1 

 



11 



10 

 

 

 6 

 6 



6-8 



12 



9 

 4 

 







5 

 24 



6 

 10 



5 

 2 



8 



15 



11 

 

 



15 



9 

 

 



7 

 8 



6-8 



8 

 5 

 5 

 2 







12 

 25 



6 



9 



1 

 3 



9 



19 



12 







7 



14 



13 

 



1 

 5 

 7 



7-9 



15 



1 

 4 

 





 11 

 24 



6 

 10 



4 



4 



9 



19 



11 



5 



8 



21 



9 

 

 3 

 6 

 10 



8-2 



8 

 2 

 

 





 13 

 27 



5 

 10 



4 



14 



18 

 10 

 12 

 4 

 17 



11 

 

 3 



9 

 14 



8-4 



4 

 4 



2 



2 



4 



13 



12 



10 



13 

 15 

 12 



7 

 9 



14 

 6 

 6 

 6 



8 



83 



15 



11 



8 



7 



7 

 13 

 25 

 25 



14 



10 



5 



12 



4 



14 



19 

 20 

 34 

 20 

 21 



22 

 12 

 12 

 12 

 14 



