1900.] 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



273 



Jan. 31. — A raven was seen at the bucket stage at 16 h . 



Feb. 1. — Raven seen on summit at 16 h . 



Feb. 2. — -Clear and sunny most of the day, but clouds 

 hanging over surrounding hilltops, and passing over " Ben " 

 occasionally. Box changed after 5 h . Height not altered. 



Feb. 5. — The summit was clear and the sky cloudless, 

 or nearly so, till 8 h , enveloped in a thin fog the rest of 

 the day. The air was saturated all morning with passing 

 fog. Lunar coronas seen at 20 h , 23 h and midnight. 

 Three ravens on summit at 14 h . 



Feb. 7. — The hilltop was clear most of the day, but 

 fog lay thickly on the surrounding hills, and was passing 

 over the Ben very frequently. Lunar coronas at 2 h , 18 h 

 and 19 h , and a lunar halo at 23 h . Box changed after 10 h . 



Feb. 8.— Clear, and air very dry till 10 h . Fog till 21 h , 

 and clear again till midnight. The humidity was as low 

 as 30 per cent, at 6 h . In the early morning, the air 

 being very clear, a number of the west coast lights were 

 seen. 



Feb. 9. — Cloudless at l h , fog till 14 h , clear and sky 

 slightly clouded thereafter. A lunar corona at l h and a 

 lunar halo at 20 h . After 20 h and on till midnight a 

 number of the west coast lights, including Ushenish ? 

 (S. Uist), Barra Head, and Skerryvore, were distinctly 

 seen. 



Feb. 10. — Temperature very low and sky absolutely 

 cloudless all day. Fog lay over the Caledonian Canal 

 and Locheil all forenoon, disappearing after 12 h . The 

 west coast lights were distinctly seen in early morning 

 and again at night. 



Feb. 11. — Temperature still low but rising slightly, sky 

 practically cloudless, and the highest possible visibility 

 observed most of the day. Fog over Caledonian Canal 

 and Locheil, and also on surrounding hills all morning. 

 Humidity 23 per cent, at 23 h . Lunar corona at 5 h . Four 

 ravens about summit all forenoon. 



Feb. 15. — Moderate S.E. winds till 8 h , increasing 

 to gale force at 10 h and continuing with an estimated 

 velocity of 90 to 100 miles per hour till midnight ; 

 some showers of snow fell in forenoon and again 

 after 17 h , but owing to the amount of snow-drift the 

 values entered in the daily sheets are interpolations. 

 The Tower Thermometer was in use from 18 h to 23 h . 

 Barometer pumping heavily all day. 



Feb. 18. — Heavy showers of snow and snow-hail in 

 forenoon. St Elmo's fire was noted at 7 h and 8 h . 



Feb. 21. — Thermometer box changed after \\ h . At 

 8 h three snow-buntings and two ravens were seen about 

 Observatory. 



Feb. 22.— Dry and Wet bulbs changed at h 15 m . 



Feb. 25. — Thermometer box changed after 17 h ; same 

 thermometers put out. 



Feb. 26. — Cloudless till 5 h , fog till 9 h and clear again, 

 but sky slightly clouded, till 21 h . Fog lay in the valleys 

 nearly all day, but the air was dry when summit was not 

 actually enveloped in fog. 



March 1. — Fog till 10 h , cloudless thereafter, with 

 cumulus fog in valleys all round. A number of the 

 west coast lights were seen after 20 h . Thermometer box 

 changed after 13 h ; same thermometers put out again. 



March 2. — Aurora seen at l h and 2 h . Glory at 8 h . 

 Thermometer box changed after 10 h . 



March 3. — Sky cloudy most of the day. Heather was 



seen burning in valleys all round below. The west coast 

 lights were seen in early morning. Between 16 h and 17 h 

 two ravens and a snow-bunting were seen. 



March 4. — Cloudless all day, and air dry, humidity 

 being as low as 16 per cent, at l h . The west coast lights 

 were seen all evening. 



March 6. — Cloudless, with detached fog on surround- 

 ing hills all day. The coast lights were seen in early 

 morning and again at night. Three ravens seen at 15 h . 



March 7. — Cloudless till 15 u , fog passing at times 

 thereafter. Lunar coronas were seen at 19 h , 23 h and 24 h 

 and a lunar fog-bow at midnight. 



March 8. — Two ravens seen at ll h . 



March 9. — Two ravens were observed flying about the 

 summit most of the day. 



March 10. — Clear and cloudless most of the day, but 

 air saturated and fog passing. Very thick haze iay in 

 valleys, due probably to the amount of heather burning. 



March 11. — Hilltop clear at 9' 1 and 10 h and again at 

 19 h and 20 h . Fog the rest of the day. The 12 h observa- 

 tion was taken 7 m late. Dark brown fog-crystals forming 

 all day. 



March 13. — Glazed frost at 23 h and midnight. Haze 

 from E. to S. Strong earth currents on telephone at 

 21 h 30 m and 21 h 50 m . Three ravens seen at 10 h . Ther- 

 mometer box changed at 13 h 10 m . Thermometers thawed 

 and put out again. 



March 17. — Summit clear since 8 L but sky a little 

 cloudy chiefly with cirro-str. on which a lunar halo was 

 seen at 22 h , 23 h and midnight. West coast lights seen 

 at 20 h . Thermometer box changed at ll h 10 m . Same 

 thermometers put out. 



March 18.— Thin fog from 8 h till 14 h . Clear since, but 

 sky a little cloudy till 18 h ; cloudless thereafter. Fog on 

 hills to E. and S. most of the day, and at times passing 

 over summit. Lunar halo seen at l h and 3 h . 



March 19.— Sky cloudless till 4 h . Cloudy till 10 h ; 

 fog since. Fog on hills and cirrus above horizon to S. in 

 forenoon. Lunar halo seen at 5 h . 



March 20. — Summit clear till 6 h and again after 14 h , 

 but sky cloudy or overcast. Fog on hills aud thick haze 

 all round, most of the day. Air dry for a few hours in 

 early morning, lowest humidity 45 at 5 h . Lunar halo seen 

 at 3 h . Thermometer box changed at 20 h 10 m . Ther- 

 mometers thawed and put out again. 



March 21. — Summit clear at times, with short sunny 

 intervals during the day. Sky apparently cloudy or over- 

 cast and fog on hills all round. 



March 23. — Sky nearly cloudless, but considerable fog 

 on hills which enveloped summit at 15 u . Slight haze in 

 distance to S. in forenoon. A solar halo with mock suns 

 seen at 14 h . Box changed at 10 h 10 m . Thermometers 

 thawed, and put out again. 



March 24. — Summit clear frequently during the day 

 but sky cloudy; cloudless after 19 u . Fog and haze in 

 valleys most of the day. Air dry in afternoon, lowest 

 humidity 15 at 21 h . 



March 25. — Sky cloudless and air very dry at l h , the 

 humidity being 22, almost continuous fog since. 



March 28. — Thermometer box changed at 8 h 15 m « 

 Thermometers thawed and put out again. Three ravens 

 and a snow-bunting seen in the afternoon. 



March 31. — Sky cloudless till 10 11 and again after 18 h . 



