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BEN NEVIS OBSERVATORY-LOG-BOOK, 1897. 



Jan. 4. — Fog in early morning, and after 18 h mostly 

 clear, except for passing scud from fog below at times 

 in the interval. Bavens were seen at 10 h and 16 h and 

 the tracks of a fox were followed from M c Lean's steep to 

 east end of Hill. Thermometer box changed at 5 h 20 m . 

 Height not altered. 



Jan. 6. — Fog all day, forming dark fog crystals. 

 E.S.E. gale all day. Minimum force, 7. At 13 h the hand 

 anemometer was held out from tower door and registered 

 84 miles per hour : on the roof it registered 73. 



Jan. 8. — Fog and E.S.E. gale all day. At 21 h the 

 force was 10, and at midnight 11. At former hour lamp 

 was blown out twice. At midnight the drift consisted of 

 junks of ice and fog crystals, so observer did not go to 

 thermometer box. The readiug of the storm thermometer 

 in tower was entered for that hour. Since the gale 

 commenced readings of both tower and outside 

 thermometers have been made, and as they were mostly 

 identical, no correction was applied to the midnight 

 reading. 



Jan. 9. — Wind blowing hard all morning, but moderat- 

 ing to forces between 5 and 7 in evening. Fog crystals 

 have been steadily growing since the gale began on 5th, 

 and are now 5 to 6 feet long, and on tower over 8 feet. 



Jan. 10. — Summit clear in forenoon, but fog all round 

 and at times passing above. Thermometer box changed 

 after 5 h . Height not altered. Fog crystals slightly dark 

 in colour to-day. 



Jan. 12. — Fog with a few clear intervals. Lunar 

 corona and fogbow seen at midnight. It was noted that 

 immediately outside the fogbow there was a dark space — 

 distinctly darker than both the bow and the rest of the cloud 

 on which it was formed. 



Jan. 13. — Summit clear most of the day, but sky cloudy 

 or overcast. Lunar halo seen at midnight. Thermometer 

 box changed after 2 h . Height not altered. Two ravens 

 were seen in forenoon. 



Jan. 14. — Lunar corona and fog bow at 3 b and corona; 

 again at night. Tracks of a weasel seen at Hotel to-day. 



Jan. 15. — Clear most of the day, but fog below in 

 places and sky somewhat cloudy. Thermometer box 

 changed after ll h . Height not altered. Lunar corona 

 seen in early morning and at 1 8 h . 



Jan. 17. — Thick haze all day. Lunar corona at 20 h . 

 A raven seen at 13 h . 



Jan. 18. — Somewhat cloudy, and fog at times in fore- 

 noon. Clear in evening and cloudless at night. Broken fog 

 below in places chiefly to N., IST.E. and E. Glory seen on 

 distant fog at 16 h . A great number of foxes' tracks were 



seen on Cairn Liarg, and two ravens were seen there. 

 Thermometer box changed at 12 h . Height not altered. 



Jan. 19. — Cumulus fog all round below, and occasionally 

 enveloping summit. Lunar corona seen at 4 h . 



Jan. 20. — Air very dry at and after 17 h , when all the 

 clouds and fog sank beneath summit. At midnight 

 humidity was 13 per cent. 



Jan. 21. — Air very dry till 3 h . Fog thereafter. As 

 the air became saturated the temperature of wet bulb 

 rose to that of dry bulb. Thin fog was just forming on 

 summit or rising from N. corry. Yesterday when the air 

 became 'dry by fog sinking the dry bulb rose while the 

 wet continued much the same as it was in the fog. 

 Lunar halos seen at 2 h and 3 h , and coronas at 4 h , 5 h , 

 6 h , and 7 h . Squally K winds at night. 



Jan. 23. — Air became dry suddenly at 18 h , the dry 

 bulb rising 3°. At 21 h air was again saturated, the wet 

 bulb rising to temperature of dry bulb. After this hour 

 there seemed to be both fog and mist present on summit. 

 Temperature 17° to 19°. Thermometer box changed after 

 noon. Height not altered. 



Jan. 24. — At l h the envelope of cloud on summit 

 seemed to be half fog, half mist, as was observed last 

 night, and the fog crystals appeared to be partly ice, 

 partly snow. Wind W.N.W., and temperature 19 - 3 at l h . 

 Mist was noted again in forenoon, and sleet fell. Wind 

 N". and temperature about 25°. 



Jan. 29.— Summit clear from 9 h till 20 h . Sky cloudy ; 

 nearly overcast at first with cir.-str. which fell into 

 str.-cir., and later into stratus and nimbus when it 

 touched summit. For several hours before cloud reached 

 summit the air was very dry. When the air became 

 saturated the dry bulb continued steady, and wet bulb 

 rose to temperature of dry. Thermometer box changed 

 after 12 h . Height not altered. 



Feb. 1. — Sky almost cloudless till 7 h . Then cir.-cum. 

 formed and was noticed to be gradually falling during 

 forenoon until it formed stratus at noon and enveloped 

 summit all afternoon. At 10 h the humidity was 30. 

 The temperature was higher after the cloud came down 

 to summit than it had been earlier. Thermometer box 

 changed after 8' 1 . Height not altered. 



Feb. 7. — Sky perfectly cloudless and air pretty dry till 

 11 a.m. Fog below all round to about 3000 ft. at 7 a.m., 

 but rising thereafter, and at 12 h summit was enveloped; 

 continuous fog after that. Glories seen at 8 h , 9 h , 

 and 10 h . 



Feb. 8.— Wet mist from 7 h till 14 h , and again from 21 h 

 till midnight. Temperature ranging from 27°'7 to 29°-7. 



