1889.] 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



143 



apparently clear all day, but fog over the hills till 7 h , 

 especially to E. Just before sunrise, i.e., about 8 h , it rose 

 and covered Beu Nevis also, and continued more or less 

 all day. Bright auroral arch seen at 20 u during a break 

 in the fog. It extended from about N.N.E. to N.W. by 

 W. Single arch, no streamers. 



Nov. 22. — Showers of hard icy snow fell at intervals 

 all afternoon and night. Top clear at 15 h , no fog in 

 valleys. 



Nov. 23.— Thermometer box shifted at 9 h 15 m . Same 

 thermometers left out. Height not altered. Top clear 

 and sky cloudless at 19 h , but fog all round and passing. 

 The stars were seen gleaming through the fog at 22 h . 



Nov. 25. — Drift most of the day, making raingauge 

 measurements very doubtful. Thermometer box shifted 

 at 16 h 20 m . Height above snow not altered. 



Nov. 26. — Sky apparently almost clear all afternoon, 

 but fog blowing over the hill top. An aurora was seen at 

 19 h and at midnight. Heavy drift all day, though only 

 2 inches was measured at post A where the wind swept the 

 snow off. A drift, 2 to 3 feet formed on the path to the 

 thermometer box, and one about 5 feet deep in front of 

 the kitchen window. 



Nov. 27. — Aurora was seen again at l h , and also at 

 20 h . No raingauge was out to-day, but apparently no 

 snow fell though there was a good deal of drift. 



Nov. 28. — Thermometer box shifted at 9 h 10 m . 

 Height above snow not altered. In the afternoon the 

 fog became damper and at 19 h was distinctly mist, which 

 continued till 21 h , the temperature at the same time 

 being about 24°. The fog crystals at the same time 

 became harder and more icy. Very small fine snow was 

 falling at midnight. 



Nov. 29. — A lunar corona was seen at 18 h — one ring 

 complete, red outside, and a blue margin beyond. 



Nov. 30. — Clear sky above the fog seen occasionally in 

 early morning, but drizzling rain and thick mist towards 

 evening. A solar corona was seen at 12 h 15 m — two 

 complete sets of colours and part of a third ring. Red 

 outside and blue inside in each set. An observatory 

 horse was up on the 8th, 14th, 18th, and 28th of 

 November. From the 10th to the 24th of the month the 

 top was almost entirely clear of snow. 



Dec. 3. — Thick fog till 15 h depositing feathery fog 

 crystals slightly brown in colour. From 16 h onwards sky 

 clear except for cirrus and cirro-cumulus, and haze or fog 

 over the hills round. A lunar halo or portions of one 

 was seen from 20 h onwards. Radius to inner edge at 

 20 h , 22° 0'. Thermometer box shifted at 16 h 20 m . 

 Height above snow not altered. 



Dec. 4. — Haze and fog over the hills round till noon, 

 after which it rose higher and was blowing across Ben 

 Nevis all afternoon and night ; but the sky when seen 

 was clear above. Air very dry in early morning. At 3 h 

 the wind velocity by hand anemometer (2 mins.) was 

 44 miles per hour. The force recorded was 6. The sun 

 rose through the haze, but came out clearly when it got 

 above it. The first flash above the haze was green ; and 

 the recorder began to register bright sunshine as soon as 

 the disc was above the haze. At sunset the top was 

 clear. The sun set into cloud at 15 h 49 m , but no green 

 flash was seen. The earth shadow was observed at 16 h . 

 At 17 h a lunar corona, red, with faint colours inside it, 



and a blue margin outside, was seen. Radius of red 

 3° 51'. 



Dec. 5. — Top clear occasionally in forenoon, but fog 

 over all the hills round. 



Dec. 6. — Lunar corona seen on passing fog at l h . At 

 2 h sky three fourths covered with small and rather high 

 cumulus. At 3 h overcast with low, massive and thick 

 cumulus ; the latter type persisted till mist came on at 6 h . 

 Distinct rain falling at 6 h , temperature being 24° - 8. Drizzl- 

 ing rain fell at intervals during the day, though the tempera- 

 ture remained below 32°, but snow fell towards evening. 



Dec. 7.— Thermometer box shifted at 3 h 25 m . Height 

 above snow not altered. Top clear occasionally in fore- 

 noon, but fog all round, and usually blowing over the hill 

 top. Sky clear except for local clouds above the hill top. 

 Showers of heavy rounded snow in afternoon and evening. 

 A horse was up to-day with stores. 



Dec. 9. — Heavy rain fell till 9 h , and showers of snow 

 all afternoon. The snow was hard and dry. 



Dec. 11. — A distinct shower of sleet fell at 19 h , though 

 the sky was apparently clear above the thin fog on the hill 

 top, and the temperature was 17°*3. At 22 1 ' it was mist and 

 quite damp with a temperature of 18° "8. Thermometer 

 box shifted at 14 h 20 m . Height above snow not altered. 



Dec. 12. — Clear sky but fog blowing over the hill top 

 till 8 h . Lunar corona seen on this fog. S. or S.E. gale 

 from 17 h onwards with heavy drift. The low level door 

 had to be closed at 18 h . At 21 h 30 m an attempt to 

 measure the velocity of the wind by the hand anemometer 

 was made : but the cups were blown off, the shank break- 

 ing immediately under the crossbars. When it gave way 

 it had recorded 

 wind was increasing during the time 



Dec. 13. — At l h the wind moderated, and snow was 

 falling heavily, so a gauge was put out for the first time. 

 Heavy snow fell all forenoon, covering the hill top about 

 2 feet deep in some parts, but there was almost no drift. 



Dec. 14.- — A lunar corona and fog-bow were seen at 2 h , 

 when the fog thinned for a few minutes. Thermometer 

 box shifted at 4 h 20 m . Height above snow not altered. 

 The measurements of snow-fall in the forenoon are very 

 uncertain owing to drift. No gauge was in use from 

 noon to 20 h , but apparently no snow or rain fell until 

 shortly before 20 h . 



Dec. 15.— Thermometer box shifted at 12 h 20 m . 

 Height above snow not altered. Sky partly covered with 

 cirro-cumulus when seen in afternoon, but mist and rain 

 came on before midnight. 



Dec. 16.— Thermometer box shifted at 10 h 25 m . 

 Height above snow not altered. Some hard icy drift was 

 flying about at 22 h . 



Dec. 20. — Fog all day but stars seen through it at 6 h 

 and 7 h . At 19 h St. Elmo's Fire seen on wind vnne, tower 

 chimney, and kitchen chimney ; also on observer's pencil 

 and hair. Not very bright. Gone at 19 h 30 m . 



Dec. 21.— Thermometer box shifted at 16 h 25 m . Box 

 put one stage higher on ladder stand. At 16 h faint 

 after-glow seen to S.W., and earth shadow to N.E. 

 Wind was northerly in afternoon. Calm at 20 h , and S.E. 

 after that. From 17 h to 23 h the air was dry, the humidity 

 at 20 k was computed at 12; the barometer was also at a 

 maximum at 20 h . The south side of the house is now deeply 

 buried in drift, the kitchen window needing to be partly 



1^ mile in about 50 seconds, and the 



