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BEN NEVIS OBSERVATORY-LOG-BOOK, 1903. 



Jan. 3. — After 12 h the thermometer box was raised 

 one step on ladder ; height above snow 50 inches. St 

 Elmo's Fire seen at 2 h , 20 h and 22 h , very bright on each 

 occasion. 



Jan. 5. — From 7 U till 20 u the hill-top was clear, sky 

 overcast or nearly so, and the air dry and clear. Fog 

 lay over the surrounding hills most of the day. Glazed 

 frost was noted at 2 1 ', lunar coronse at 17 h , 19 h and 20 h , 

 and a lunar halo at 20 h . To-day the hourly amount of 

 sunshine was calculated from half-hour to half-hour, and 

 this method of calculation is to bo continued from now. 

 Thermometer box changed at 9 h 15 m ; height not 

 altered. 



Jan. 6. — St Elmo's Fire seen at midnight. 



Jan. 8. — In the evening the hill-top cleared, but the 

 sky was covered with stratus and cirro-stratus; after 21 h 

 the air became very dry, the humidity being as low as 

 23 per cent, at 23 h . Lunar corona? noted at 17 h , 19 h and 

 20 h , and a lunar halo at 20 h and 21 h . The thermometer 

 box was changed at 20 h 15 m ; height not altered. 



Jan. 10. — Strong squally wind till 18 h , the velocity 

 ranging from 30 to 90 or 100 miles per hour. The 

 storm thermometer in tower was read along with the 

 outside observations, and it was found that the greatest 

 difference was 0°-2, and that the mean of eight observations 

 came out the same as the readings in the Stevenson. 

 After 19 b , when the wind had fallen considerably, the 

 hill-top cleared, but fog was passing till midnight. At 23 h 

 and midnight a lunar corona was noted. 



Jan. 12. — Fog enveloped the Ben till 13 h , thereafter 

 the summit was clear and the sky absolutely cloudless till 

 midnight, but the air was, for the most part, saturated. 



Jan. 13. — Sky absolutely cloudless, except at 19 u when 

 fog was passing. Some haze lay in the surrounding 

 valleys, and patches of fog on the hills to S.E. Glories 

 seen at 15 h , and a lunar corona at 19 h . 



Jan. 15. — The sky was cloudless most of the day, and 

 a thick band of haze surrounded the horizon. 



Jan. 16. — A south east gale of hurricane force blew till 

 17 h , moderating slightly thereafter. At 2 h and 3 h the 

 temperature was read at the storm thermometer in tower. 

 The sunshine recorder having been repeatedly blown off 

 the pillar, it had to be taken inside, and the values entered 

 in the daily sheet are interpolations. During the day 

 the temperature inside the Observatory was very low; in 

 the kitchen a thermometer placed about six feet from the 

 stove, stood at 25' all evening. 



Jan. 18. — Dark brown fog-crystals forming all day. 



Jan. 19. — Clearing at times in afternoon, sky cloudless 

 after 22 h . Thermometer box changed after midnight. 

 Lunar corona at 4 h . 



Jan. 20. — AVhite fog-crystals forming all evening. 

 Lunar corona at 3 h . 



Jan. 21. — Dark brown fog-crystals forming all fore- 

 noon. Heavy showers of hail fell between 18 h and 

 midnight. 



Jan. 24. — Heavy showers of snow and hail fell during 

 the day. St Elmo's Fire seen at 6 h . 



Jan. 26. — Several flashes of sheet lightning were seen 

 at 22 h . 



Jan. 27. — Snow and snow-hail fell heavily all day. 

 Lightning noted at 2 h 30 m , and St Elmo's Fire at l h , 13 h , 

 18 h and midnight. 



Jan. 28. — St Elmo's Fire was seen at l h and 2 h ; at the 

 latter hour snow-hail was falling heavily and St Elmo 

 was exceptionally bright. 



Feb. 9. — Lunar halo at 19 h and 20 h , and corona 

 at 21 h . 



Feb. 12. — The hill-top cleared in afternoon, but the air 

 remained saturated, large bands of fog hanging about all 

 round and passing over the summit. Lunar coronae noted 

 at 21 h , 22 h and 23 h . Thermometer box changed at 15 1 ' 

 15 m . 



Feb. 15. — Some snow-buntings were seen in the after- 

 noon, and a raven was seen in the Observatory gorge 

 at 17 h . The thermometer box was changed at 9 h 15 m . 



Feb. 20.— Lightning seen at 3 h 3 m , 3 h 38 m and 3 h 44 ra . 



Feb. 25.— Lightning seen at l h 5 m . 



Feb. 27. — At 2 h , 3 h and 4 h the tower thermometer 

 readings were used because of a gale ; the tower 

 readings were found to agree closely with those of the 

 Stevenson Screen. 



March 1. — At 19 u 15 m the thermometer box was 

 changed. Height above snow (39 inches) not altered. 



March 3. — The summit was clear and the sky cloud- 

 less in the early morning and again for a few hours in 

 the afternoon. From 16 h till 18 u the air was very dry. 

 At 3 h 15 m the thermometer box was changed; the 

 box was raised one step on ladder. At 15 h 15 m the 

 box was again changed. Height above snow at 15 h , 

 61 inches. 



March 5. — At l 1 ' St Elmo's Fire was noted, and 

 lightning was seen at 2 h 8 m . 



March 7. — The thermometer box was changed after 

 7 h . Height above snow not altered. 



March 8. — Lunar coronse noted at l h and 2 h . The 

 thermometers were changed after 15 h . 



March 10. — The thermometers were changed at 12 h 

 15 m . Height above snow not altered. 



March 11. — The summit of the hill is one mass of 

 mounds and furrows, and hour after hour during the 

 evening showed a change in the position of the snow- 

 wreaths. After 22 h there was a trench near the 

 thermometer box, and the snow walls on both sides of it 

 were about five feet high ; this all disappeared before 

 midnight. 



