1902.] 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



461 



Nov. 3. — Hail — small icy pellets — falling at 10 h . Fog- 

 crystals forming at night. 



Nov. 5. — Fog-crystals forming — a glassy kind that gave 

 a metallic sound on being struck or broken. 



Nov. 6. — Glories observed at 15 h 35 m . Two measure- 

 ments of radius of red gave 5° 59' and 5° 54'. 



Nov. 7. — Stormy all morning. At 4 h it was too bad 

 to go outside, so the temperature was read from storm 

 thermometer in tower. Eight previous readings gave a 

 correction of — 0°"1, and this was applied to the 4 h 

 reading. 



Nov. 13. — Lunar coronse seen at 22 h and midnight. 



Nov. 14. — Lunar corona (rad. of outside of red 2° 35') 

 seen at l h . Fog-crystals forming at times. 



Nov. 15. — Fog or mist with short clear intervals all 

 day. Lunar halo seen at 21 h and 23 h . Two ravens 

 heard in cliff. Glories and fog-bows seen between ll h 

 and 12 b . Mist very thick and dry. Although conditions 

 seemed favourable for a brilliant display, yet only one 

 series of colours was seen, except once a second red was 

 observed, but was gone before it could be measured. The 

 fog-bow was white and very broad. 



Order of colour in glory. — White, blue, yellow, 

 red 1 — red 2 . 



Measurements : — 



Outside of Red 1 . 

 5° 26' 

 5° 26' 

 5° 57' 

 6° 2' 



Inside of Red 1 . 

 4° 23' 



Fog-bow. 

 Inside 38° 5' 

 Outside 45° 0' 



Nov. 16. — Thick fog or mist. Icy fog-crystals in fore- 

 noon and ordinary crystals in evening. Peculiar reddish 

 glow in very thick mist at 7 h . 



Nov. 17. — Fog till 9 h . Cir.-c. and hard-packed cir.-s. or 

 str.-c. on sky till 16 h . Sky cloudless after 17 h . A white 

 weasel was seen near thermometer box at 16 h . 



Nov. 18. — Sky cloudless except for a little scud at 23 h . 

 Bright afterglow noted. Cold band strong in spectrum in 

 afternoon. Haze below, and fog seen to E. and S.E. in 

 forenoon. 



Nov. 20. — Fog on summit, but sky apparently cloudless. 

 Lunar corona at midnight. 



Nov. 21. — Thin fog in morning. Cloudless all even- 

 ing. Shadow of Ben seen at 8 h and glories at 10 h . A 

 white weasel was seen at 14 h to southward of Observatory. 

 Dark copper colour under moon at midnight ; colour just 

 above horizon, the moon being low. 



Nov. 23. — Tracks of weasel seen on snow to-day. 



Nov. 24.— Fog most of the day. At 22 h , 23 h , and 24 h 

 it was difficult to determine whether it was fog or mist. 

 The same was noted at ll h yesterday. Clear ice forming 

 at midnight. Snow-bunting seen at 8 h . 



Nov. 26 — Mist, with slight drizzle at times. The tem- 

 perature to-day was remarkably steady, being 32° most of 

 the day, and only rising to 32°-6 at night. The deposit 

 on windward side of everything to-day consisted of clear, 

 very sharp-pointed, but ragged-looking ice. One peculiar- 

 ity about it was that it was always growing, and yet 

 seemed to be thawing, being always wet. 



Nov. 27. — The above sort of ice continued forming till 

 5 h to-day, when the deposit began to be less clear. At 6 h 

 the tips were quite white, with ordinary fog-crystals. In 



clear intervals in afternoon it was noted that the sky was 

 overcast, with cir.-s. lying N.W. and S.E. Some hard- 

 packed str.-cir. was also seen. 



Nov. 28.— S.E. gale till 7 h , with sharp, icy drift. There 

 is a thick icy crust on everything, including the former 

 growth of fog-crystals. This growth is from 6 inches to 

 2 feet long. 



Dec. 1.— Gale all day, E.S.E. or S.E. by E. From 2 h 

 to 4 h , and at and after 16 h , the storm thermometer in 

 tower was used. It was found that no correction was 

 necessary on its readings. Fog-crystals forming all day. 

 Between 7 h and ll h these were ice, mist being on 

 summit — not fog. 



Dec. 2. — The gale moderated by 6 h to-day. There are 

 wreaths of snow from 2 to 3 feet deep about the Obser- 

 vatory, although only 7 inches at snow-gauge. At the 

 bucket stage there is a cornice on edge of cliff fully 6 feet 

 long. Tracks of weasel seen on snow to-day. 



Dec. 7. — Sky cloudless till 6 h ; cloudy and at times 

 overcast since with cir.-cum. Slight haze below all day; 

 thickest to westward. A raven seen at 13 h . 



Dec. 8. — Sky cloudy in forenoon, but cloudless all 

 afternoon. Some detached fog on hills to East and 

 South almost all day, rising up in the evening and passing 

 over summit at times. Air very dry all day ; the lowest 

 humidity was 13 at 16 h . The shadow of the Ben seen at 

 9 h , and the earth shadow between 15 h and 16 h . Snow- 

 buntings seen during the day. 



Dec. 9.— Very thin fog till 14 h ; clear till 21 h ; but sky 

 cloudy, with cir.-cum. and hard-packed cir.-str. moving 

 pretty smartly from E. and E.S.E. Fog during the rest 

 of the evening. Air dry from 16 h to 21 h ; very dry at 

 18 h , the humidity being then 16 per cent. 



Dec. 11. — Summit clear most of the day and sky 

 almost cloudless, cir.-s. forming after 21 h , on which a 

 lunar halo was seen at 22 h , 23 h , and midnight. Solar 

 coronse seen frequently during the day. Fog on hills all 

 day except to N., and passing occasionally over hill-top. 



Dec. 12. — Sky cloudy most of the day. Fog hanging 

 about hills all day ; rising up and finally settling on 

 summit about midnight. 



Dec. 13. — Earth currents in telegraph cable between 

 18 h 40 m and 18 h 50 m . 



Dec. 14. — Lunar halo at 4 h and 5 h . Earth currents in 

 telegraph cable at 23 h 8 m . 



Dec. 16. — Wind backed to S.E. and blew a strong gale 

 till 5 h . From 2 h till 4 h readings were taken from storm 

 thermometer box in tower. No correction was applied. 



Dec. 19. — Glazed frost all afternoon, the temperature 

 being 30° to 31°. 



Dec. 21. — Mist with drizzling rain till 14 h ; clear since, 

 the mist sinking below summit to about 4000 feet. 

 Temperature at the same time rose 5°'4 and continued 

 rising during the rest of the evening. Air very dry since 

 15 h . Earth shadow seen at 15 h 40 m . 



Dec. 22. — A little cirrus and cir.-c. on sky during the 

 day, moving slowly from N. Fog all round to about 

 4000 feet all day. Aurora seen with shifting streamers 

 at 22 b . 



Dec. 23. — Aurora at l h and a lunar corona at 6 h and 7 h . 



Dec. 25.— St Elmo's Fire seen at 18 h . 



Dec. 28. — The summit was clear at intervals about 

 mid-day, and thick haze lay in the valleys. Thunder was 



TRANS. ROY. SOC. EDIN. — VOL. XLIV, 



3n 



