1899.] 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



181 



Jan. 31. — Summit clear at 4 h and till 6 h , but sky 

 cloudy and fog all round to 4000 feet and passing over 

 summit at 6 h . Summit again clear at 22 h and midnight, 

 and sky almost cloudless, but great banks of fog all round, 

 rising higher than the hill-top and passing over the summit 

 frequently. 



Feb. 1. — Sky cloudless at midnight, but thick fog all 

 round, high up, and passing. Thermometer box changed 

 at 12 h 10 m . Height above snow 44 inches. 



Feb. 2. — Summit clear from 2 h till 1 l h , except for 

 some fog passing at times, and sky cloudless. Thin fog 

 since 12 h , the sky overhead being seen frequently and 

 apparently cloudless. Thermometers changed at 8 h 12 m . 



Feb. 3. — Temperature low and showing fair range 

 (22°'6 to 14° - 0). Sky cloudless at midnight and ap- 

 parently a good deal of fog all round. Light N. or 

 NE. winds till 10 h . Calm since. 



Feb. 4. — Sky cloudless till 5 h , and almost cloudless 

 again after 15 h . Detached fog on hills and passing over 

 summit at intervals. Somewhat hazy below all round. 

 Thermometer box changed at h ll m . 



Feb. 5. — Fog off and on summit all day and sky 

 slightly cloudy in forenoon, but apparently cloudless from 

 17 h till 22 h . 



Feb. 9.— Thermometer box shifted at 15 h 15 m . Height 

 above snow 42 inches. 



Feb. 10. — Thermometer box changed at 9 h 10™. 

 Height not altered. 



Feb. 11. — Temperature at or slightly below 32° all 

 day, with showers of snow, sleet, drizzle, and hail. 

 Squally S.W. winds till 14 h , backing to S.E. and 

 increasing to a gale in the evening. 



Feb. 12. — Summit clear at I7 h , but sky a little cloudy. 

 Summit again clear at midnight and sky cloudless. Very 

 bright aurora seen at midnight. 



Feb. 13. — Thermometer box changed at h 10 m , and 

 raised one step up. Thermometers changed only again at 

 20 h . Height above snow 51 inches. 



Feb. 14. — Strong earth currents on telephone between 

 23 h and midnight, and bell ringing occasionally. Lightning 

 seen at midnight. 



Feb. 18. — Fog with slight showers of snow till 16 h , 

 clear since, but sky somewhat cloudy with cir. and cir.-str. 

 Detached fog on hills, rising higher than hilltop and 

 passing over summit to E. Lunar halo seen at 20 h , 21 h , 

 23 h , and midnight. Thermometer box changed at 

 17 h 15 m . Height above snow 47 inches. 



Feb. 19. — Sky cloudless or nearly so all day. Detached 

 fog hanging about hills, but clearing away in afternoon ; 

 by 18 b no fog visible below. Air dry all day and very 

 dry towards evening. The air also has been remarkably 

 clear, the Outer Hebrides being seen frequently during 

 the day. 



Feb. 20. — Sky cloudless till 16 h , cloudy with cir.-cum. 

 and hard packed cir.-str. till 21 h , fog since. Fog over 

 Caledonian Canal and hills to S. in forenoon, and on hills 

 to E. and S.E. in afternoon. Air very clear and dry most 

 of the day; lowest humidity 16 at 7 h . Top joint of 

 thermometer ladder fixed up after 16\ 



Feb. 21. — Continuous fog till 9 h . Summit clear at 

 times till 14 h , clear since, but sky cloudy with cir.-s., on 

 which a lunar halo was observed at 19 h , 20 h , 21 h , and 

 22 h . Haze all round below in afternoon. 



TRANS. ROY. SOC. BDIN. — VOL. XLIV. 



Feb. 22. — Almost cloudless sky all day. No fog below, 

 but some haze in valleys most of the day. Lunar halo 

 seen at 22 h and 23 h . 



Feb. 23. — A little cir. on sky almost all day, and thick 

 haze all round below. 



Feb. 24. — Thick haze all round below. Heavy banks 

 of fog on hills to W. at 2 h , advancing and spreading all 

 round during the forenoon; at 21 h it began to pass over 

 summit, and at 23 h had settled down on hilltop. 



Feb. 25. — Fog off and on summit till 13 h , sky cloudless 

 since. Fog aind thick haze on hills all round. Air very 

 dry at midnight, the humidity being 19. Brown fog 

 crystals forming in early morning. 



Feb. 26. — Cloudless all day down to horizon. Thick 

 haze all round, but sinking during the day and thining 

 to S. and E. in the evening. Air very dry all day. 

 Humidity ranging between 22 and 48. 



Feb. 27. — Sky cloudless till 14 h , a little cloudy since. 

 Fog on hills to W. all afternoon. Air very dry at times, 

 lowest humidity 21 at 4 h . 



Feb. 28. — Sky cloudy or overcast with cir.-c. moving 

 rapidly from W. till 7 h . Fog on hills in early morning 

 to westward, which gradually spread all round and en- 

 veloped summit at 8 h . 



March 4. — Thermometer box changed 12 h 15 m . 

 Height not altered. 



March 6. — The hissing noise which accompanies St 

 Elmo's Fire was heard at 13 h . At 15 h the depth of snow 

 was 62 inches, an increase of 10 inches during the previous 

 24 h . The increase is chiefly due to drift, which has 

 formed deep wreaths between tower and snow post. 



March 7. — Summit clear at 17 h , but sky cloudy with 

 cir. and cir.-s., and fog lying in valleys and on hills all 

 round to 4000 feet. Thermometer box changed at 

 17 h 15 m . Height not altered. 



March 10. — At 4 h the stars were seen through the fog, 

 and at 5 h it was clear to N., and shifting streamers of the 

 aurora were seen. 



March 15. — Very thin mist passing over hilltop at 7 h 

 and 8 h , on which was seen a fog-bow. Summit again 

 clear at 15 h , and sky almost cloudless since, but thick fog 

 lying in valleys and on hills all round to 4000 feet. 

 Thermometer box changed at 16 h 10 m . 



March 16. — Sky cloudless down to horizon all day. 

 Fog and haze in valleys all round, but the former 

 cleared away during the forenoon. Air very dry all day, 

 the humidity ranging between 28 and 47. Aurora seen 

 at 2 h , 3 !l , and 4 h . 



March 17. — Cloudless till 19 h , fog since. Thick haze 

 in valleys all round. Fog rising in Glen Nevis and also 

 to westward in afternoon. 



March 18. — Thermometer box changed at 12 h 10 m . 

 Height not altered. 



March 20. — Lunar coronse seen at midnight. Ther- 

 mometer changed at 13 h 10™. Height not altered. 



March 21. — Aurora seen at 20 h and midnight. 



March 22. — Aurora seen at 4 h . 



March 28.— St Elmo's Fire seen at 21 h . 



March 30. — Clear at times between 6 h and 16 h . Glazed 

 frost at l h and 2 h . Solar halo at ll h 15 m , 12 h , and 14\ 

 The cirrus on which the halos were seen was lying 

 W.N.W.-E.N.E. Snow-bunting seen at 18\ Ther- 

 mometer box changed at 7 h 10 m . Height not altered. 



2 A 



