BEN NEVIS OBSERVATORY.-LOG-BOOK, 1889. 



Jan. 1. — Fog till 6 h and cloudless sky for the rest of 

 the day, but thin fog was capping summit at several hours 

 in afternoon. The thermometer box was shifted at 8 h 

 30 m . At 13 h and 14 h double fogbows were seen; at the 

 latter hour the bow was triple at times. At 19 h , 20 h , and 

 21 h aurora was seen. At 21 h it consisted of a single well 

 defined arch, stretching from N.W. to N.N.E., and at its 

 highest point was about 7° above horizon. 



Jan. 2. — Till 3 U the sky was cloudless, but thin fog was 

 passing the summit. The aurora was seen at l h . Thick 

 fog enveloped the top from 4 h till 16 h ., and mist there- 

 after. The fog was very white, dry, and dense all morning, 

 though there was a bluish tint overhead most of the time. 



Jan. 3. — The temperature was about 31° all day, but 

 small drizzling rain was falling which formed an icy crust 

 on all exposed surfaces. 



Jan. 4. — At night it was noted that the icy crust on 

 all surfaces was distinctly sonorous, emitting a musical note 

 when struck. This crust consisted of feathery formations 

 like those formed by fog-crystals, but not so delicate in 

 texture as these, and seemed to be a mixture of snow and 

 ice. 



Jan. 6. — At 13 h 15 m the thermometer box was shifted. 

 The box was raised one step on ladder stand. The top 

 was clear at 8 h , 16 h , and 17 h . Fog very thin all day. 



Jan. 7. — The top was clear from 6 h till noon. Fog 

 lay on the hills to E. and S. most of the forenoon. At 

 12 h a gloomy appearance was observed to W. and S.W. 



Jan. 8. — The values for the amount of rain or snow on 

 doily and monthly sheets for the hours from 2 to 9 in- 

 clusive to-day are interpolations. At these hours the drift 

 rendered the working of the raingauge useless. 



Jan. 9. — At 6 h St. Elmo's Fire was seen on tower and 

 kitchen chimney. There were about a dozen different 

 brushes on tower, each about 2in. long. On kitchen 

 chimney besides the brushes on top of cowl, there was 

 one on a piece of snow that projected about a foot from 

 chimney two feet from the top. Fizzing sound heard ; on 

 raising an ice-axe, the Fire was seen on its upper end, and 

 a slight current felt in the arm holding it. Elakey snow 

 falling at the time. St. Elmo's Fire was heard on the 

 observer's hat, hair, and pencil at 13 h , but nothing could 

 be seen. 



Jan. 10. — Thin fog on top till 7 h , but top clear and 

 sky cloudless thereafter till 23 h . Haze in valleys most 

 of the day, and Stratus-fog on western hills in afternoon. 

 A fogbow, glory, and solar corona were seen at 9 h . The 

 corona was triple. Measurements of radii of rings as got 

 by stephanome were : — ■ 



1st r i n g i° 5i' 



2nd |( 2° 47' and 3° 



3 rd ,, 5° 34' 



5' 30" r measurements not very good. 



The thermometer box was shifted after the 10 h observa- 

 tion. The earth and Ben shadows were seen at 16 h . 

 At 19 h a faint milkiuess in N. sky to about 15° altitude 

 was supposed to have been auroral. After 20 h , cirrus 

 stripes were seen near W. and N.W. horizon lying 

 S.W. to N.E. 



Jan. 11. — During the last two days a considerable 

 depth of soft, loose snow lay on the summit, and to-day 

 it drifted heavily — a moderate gale having blown almost 

 all day. No fresh snow was falling to-day apparently. 

 The top was clear for short intervals in afternoon and 

 evening, showing a sky heavily clouded with cumulo- 

 stratus. 



Jan. 12. — Thin fog on top or passing all day. Lunar 

 coronse were seen at 19 h and 21 h , at the latter hour the 

 corona was triple. The 6 h observation was made 3 m late. 



Jan. 13.— Thin fog till 3 h , at 14 h and 15 h , and after 

 18 h , but fog on the lower hills all day. The thermometer 

 box was shifted after the 5 h observation. The wet-bulb 

 had not been wetted till 5 h 45 m , and at 6 h the reading 

 was unsatisfactory, being higher than that of dry-bulb. 

 Extra readings were taken at 6 h 15 m and 6 h 30 m , and the 

 former are those entered at 6 h on daily sheet. A solar 

 halo was seen at ll h and 12 h , and lunar corona? at 2 h , 3 h , 

 4 h , 21 h , and 22 h , double at times. The radiating points 

 of the cirrus to-day were N. and S. 



Jan. 14. — A lunar halo was seen at 3 h . The 21 h 

 observation was taken at 21 h 4 m . 



Jan. 16. — Fog crystals, slightly brown, forming all 

 morniug. At 19 h the raingauge was found half buried 

 in drift. The reading for that hour is probably correct, 

 though doubtful. 



Jan. 17. — The amounts of snow entered at 12 h , 13 h , 

 and 14' 1 on to-day's sheet are interpolations. At 12 h and 

 13 h the raingauge was each time completely buried in 

 snow, and during the hour, 13 h -14 h , no gauge was out. 

 Ice forming on surfaces after 18 b . 



Jan. 18. — Kaining heavily all morning, and hail, sleet, 

 or snow falling in afternoon. Peculiarly shaped hail- 

 stones fell in the first shower after the rain had ceased. 

 Each consisted of a core of dry snow, encased, except on 

 top, in an icy crust. The top showed the hexagonal 

 shape of an ordinary snow-flake. 



Jan. 18. — The summit was clear at 13 h , and for short 

 intervals during the afternoon. Between 2 h and 3 h this 

 morning the observer was down near Buchan's Wei), and 

 both on outward and homeward journey a steady westerly 

 wind of force 5, was experienced between the First Gorge 

 and Buchan's Well, while on the summit the wind Avas 

 N.W. to N., and very variable and squally. 



Jan. 20. — Top clear at times in forenoon. The ther- 

 mometer box was shifted at 10 h 30 m . At l h and 2 h 



