326 



BEN NEVIS OBSERVATORY.— LOG-BOOK. 



[1884-85. 



No other colours visible. Outside radius, 3° 25'. The glare 

 at the same time had increased to about 15° radius. 



Dec. 29. — At 3 h the sky under the moon was copper 

 coloured. Corona at 20 h red outside. Radius of red, 3° 28'. 



At 23 h double corona, colours as in margin. 

 Outer red very faint. Rather misty look- 

 ing, the size appeared to vary. Radii of 

 inner red, by stephanome, 3° 40' and 3° 55'. 



Red 



Blue 



Red 



Blue 



Yellow 



D 



1885. 



Jan. 1. — Snow crystals forming all day at from 1 to 2 

 inches per hour. The tower chimney was several times 

 choked by crystals forming under the small inside cowl. 



Jan. 2. — Very wild sunrise. At 8 b the S.E. horizon 

 bright red and yellow, with cir.-str. above tinged with 

 brown-red on lower surface. At 9 h this colour or glow had 

 disappeared, except to N.W. ; the sun was about 5° above 

 horizon, clouds dense and watery. 



Jan. 8. — At 2 h rain-gauge not found, probably blown 

 over the north cliff. 



Jan. 11. — At 9 h rain-gauge blown away. At ll h ther- 

 mometer box shifted. The snow drift blown up the cliff 

 near the plateau of storms was seen to rise from 100 to 

 200 feet in the air, and pass away to leeward in clouds, re- 

 sembling ordinary small scud clouds. 



Jan. 12. — Thermometer box shifted at 14 h . 



Jan. 14. — Bright sunrise colours, but no upper glow in 

 sky. At 10 h hazy rosy corona at sun. At 16 h E. sky 

 showed colour like afterglow. At 18 h , however, there was a 

 faint red and pale green glow above western horizon. 



Jan. 15. — Began to use new pattern rain-gauges. No 

 upper glow at sunrise. During the day brown haze round 

 sun, strongest below it. At 16 h 30 m no afterglow to 

 W., but faint glow to E.N.E. At 6 l1 40 m the western 

 afterglow began, and the eastern glow disappeared. At 6 h 

 50 m the afterglow was distinct to westward. At 7 h it was 

 fading. 



Jan. 19. — At 17 h (after sunset) red, yellow, and green 

 to westward. No upper glow. At 18 h pale blue glow to 

 westward. At 19 u pale blue glare round moon. 



Jan. 20. — In morning, fog all over lower hills. At 8 h 

 bright pink upper glow above red, and yellow colours to 

 S.E. At 10 11 and ll h red haze below sun, and white 

 glare round it. At 1 2 h hazy red corona round sun, with 

 white watery looking core. The red or copper colour 

 under the sun got fainter in the afternoon. No afterglow 

 atsunset. 



Jan. 21. — Sunrise colours very bright, but no upper 

 glow. Copper haze at sun all day. Passing fog prevented 

 sunset from being observed, but apparently there was no 

 afterglow. 



Jan. 23. — Valleys filled with haze, rising to a definite 

 level. At 18 h lunar corona observed, red outside. 

 Radius of red, 2° 36'. Again at 23 h faint misty blue look 

 round moon, no other colours. 



Jan. 24. — At 22 h faint misty corona, red outside. 

 Radius of red, 2° 30'. 



Jan. 29. — At l h and 2 h very small misty corona. At 

 £ ed 4 h misty corona. Colours as in margin. 



Blue Outer red very faint, making the blue look 



Bed more like the margin often seen, than a 



Yellow p ar t f corona proper. Radius of inner red 



= 2° 14', outer red = 3° 38'. At 21 h faint 

 bluish corona formed on scud. 



Red 

 Blue 

 Red 



White space 



3) 



Jan. 31. — Both to-day and yesterday thermometer box 

 badly choked with fine drift. 



Feb. 2.— Thermometer box shifted at 14 h . At 22 h St 

 Elmo's fire observed on tips of lightning rod ; each tip 

 having a spark like a match when just struck on it. 



Feb. 4. — At 7 h 5 m double corona observed. Colours as 

 in margin. Radius of inner red = 2° 36', 

 outer red = 5° 10'. At 8' 1 upper glow to 

 S.E., forming an arch with a watery core ; 

 the arch measuring about 14° inside radius, 

 and 30° outside, by stephanome, and being 

 coloured the usual pinkish brown hue. At 10 h rosy corona 

 round sun. 



Feb. 6. — Drift very bad all day. At 14 h a wave of 

 drift had formed between the thermometer box and the 

 tower — the box was half buried, although at 13 h it had 

 been 30 or 40 inches clear of the snow. The front of the 

 wave formed a steep bank, almost vertical, about 30 inches 

 high, which in the afternoon gradually advanced almost to 

 the tower. At 14 h the rain-gauge was also buried with 6 

 or 7 inches of snow over it. 



Feb. 7. — As the thermometer box was on the highest 

 joint of the ladder stand it could not be shifted till 17 h 

 to-day, when the wind having moderated, an extra joint 

 was fixed to ladder, and the box set 50 inches above snow. 



Feb. 8. — At 14 h barometer pumping with long slow 

 motion, falling during gusts. 



Feb. 9. — At 7 h double corona in cloudless sky. Inner 

 ring too small for stephanome, and outer too faint. At 9 h 

 thermometer box shifted. 



Feb. 10. —In morning snow crystals white, but at 17 h 

 brown ones began to form. 



Feb. 16. — At 5 h four lighthouses seen ; probably Barra 

 Head, Dhuheartach, Fladda, and one to the east of Jura, 

 not identified. At 6 h a cone or triangle of green light 

 was seen to eastward, rising to about 30° from a base reach- 

 ing from N.E. to S.E. Air very clear all morning. At 9' 1 

 copper colour under sun. At 10 h Beauly Firth seen dis- 

 tinctly. The copper colour at the sun formed a rude 

 corona. Sun set at about 17 h 34 m ; the sunset colours 

 were weak, but the sky above them was smoky green, 

 while to eastward it was deep blue. No afterglow, except 

 at 20' 1 , when a faint white glow was seen to westward, 

 possibly the zodiacal light. Faint badly defined aurora 

 at night. 



Feb. 17. — Sky very hazy and watery in early morning. 

 No upper glow before sunrise. Fog came on during the 

 day, occasionally rising and forming a pallium overhead. 



Feb. 18. — Faint copper colour below sun all day. At 

 23 h and midnight faint auroral arch from N.E. to W.N.W., 

 badly defined, no streamers. 



Feb. 19. — At 21 h lunar corona observed. Bed 

 Colours as in margin. Radius of red, Yellowish 

 2° 30'. D 



