322 



BEN NEVIS OBSERVATORY.— LOG-BOOK. 



[1884. 



Red 2 

 Blue a 

 Red 1 

 Yellow 

 Blue 1 



June S. — At 23 h snow crystals began to form on 

 thermometer box. At midnight lunar corona seen, red 

 outside, with blue margin beyond. Radius of red 2° - 30. 

 Very misty; size apparently varying. N.B. This arrange- 

 ment of colours probably explains the entry, on June 3, of 

 a solar corona with blue outside red. 



June 9. — At l h double lunar corona observed. Colours 

 as in margin. The inner one had all the 

 gradations of spectroscopic colours, the 

 outer only blue and faint red. Radius of 

 inner red ring 2°, outer 4°. When scud 

 passed over the hill top the corona was 

 hidden. At 2 h the inner rings observed 

 as before ; but the outer blue and red were not visible. 

 During the afternoon the whole sky was covered with a 

 pallium of cum.-str. clouds. The horizon was clear, and 

 the sun was seen to be shining on the western sea and 

 islands. Rum, Canna, north-west of Mull, and the Outer 

 Hebrides looked as if they were slightly raised by refrac- 

 tion. 



June 10. — At 7 h all the surrounding hills were buried 

 in white fog. Cir.-str. seen at 8 h 10 m moving from N.W. 

 Mist came on at 13 h , and lasted till near midnight, when 

 the air suddenly^ became very dry, with a strong S.W. 

 wind. 



June 11. — Short period of cold and drought, with strong 

 south-westerly wind up to 3 h . Dry and wet at 2 h beyond 

 Glaisher's tables. In afternoon James Miller found a 

 flower growing on the rocks at the edge of the north cliff 

 opposite the large cairn. 



June 12. — All night the thermometer box was covered 

 with glazing of ice. At 16 h the cage for instruments (5 

 feet high) was seen for the first time this year. 



June 13. — Thermometer box shifted at 3 h . 



June 14. — All night the thermometer box was covered 

 with ice crystals. 



June 16. — Very misty ; the mist being thicker on sides 

 of hill, but wetter on top. 



June 17. — Foggy till 17 h 30 m , when top cleared, and 

 mist sank below 3000 feet line. All the evening nothing 

 was to be seen except a few hill tops rising through the 

 clouds. This cloud was very level as a whole on its upper 

 surface, but broken into many small billowy ridges. 

 After sunset the sky just above this cloud to N.W. was 

 blood-red, with yellow, green, and blue above. These 

 colours continued all night, following the sun round from 

 N.W. to N.E., and only disappeared at sunrise. At 19 h 

 double or triple glories seen at east end of hill top. 

 Colours as in fig. 2. No. 1 was very indistinct, a mere 

 blotch of colour. No. 2 was the brightest of them. 

 No. 3 was not so bright as No. 2, and sometimes was not 

 seen ; but, when visible, was quite sharp and distinct. 



The following measurements were taken by steph- 

 anome. 



Rod (2) Bine (2) Red (3) 

 R.T.O. . . 1° 55' 1° 50' 3° 10' 



A.R. ... 1° 55' 3° 30' 



The glories were formed on the upper surface of the 

 cloud layer mentioned above. 



June 18. — The upper surface of the cloud layer sur- 

 rounding hill was very level, and it came Hush up against 

 the sides of the hill without rising or falling, just like a 

 sheet of water. About 7 h this cloud was rising bodily, 

 and just before it reached the level of the hill top a thin 



Blue 



Purple 



Green 



Bed 



Horizon 



wet mist came over the top from the north. At the same 

 time glories were seen. At 8 h double fog-bow with faint 

 glory round shadow of observer in centre seen. About £ 

 of the circles were visible (270°), the rest being cut off by 

 the shadow of the hill. Colours as noted in fig. 3. The 

 inner (fog) bow was narrower, and not so distinctly 

 coloured as the outermost. These bows were too large to 

 measure by stephanome ; they looked about the size of 

 rainbows. 



June 20. — At 15 h the hill was surrounded by fog, 

 standing high above the top, but not resting on the sides 

 of the hill. At 23 h the sky cleared overhead, the clouds 

 apparently thinning away gradually without moving. 



June 21. — Heavy dew and hoarfrost in early morning. 



June 23. — At 4 1 ' 15 m a 5-inch rain gauge was put out 

 about 700 inches E.N.E. from cage — to be read hourly. 



June 25. — All the early morning the wind was northerly 

 and pretty strong. Coming up over the cliff it broke into 

 eddies, the back-swirls of which, though not as strong as 

 the true wind, were very distinct. 



June 26. — At 20 h 20 m top cleared, leaving sky with 

 cum.-str. (10) over it. Dense white fog covered western 

 hills, and filled valleys to E. The sky gradually cleared, 

 but fog came on again at midnight. 



June 27. — At sunset the sky was 

 coloured as in margin, with rays shooting 

 upwards of pinkish colour to about 20°. 

 At midnight the northern sky was still red, 

 yellow, and green, above the haze. No fog in valleys. 



June 28. — Thick haze all round. At midnight the sky 

 was scarcely coloured to the north at all. 



June 29. — Though the sky was clear, the sunrise colours 

 were very faint. In afternoon wind blowing up from Glen 

 Nevis formed fog a little below Wragge's well. 



June 30. — At midnight observed very low-lying white 

 fog in Glen Nevis. 



July 2. — At midnight long streamers radiating from 

 the zenith were observed. They seemed to be composed 

 of filmy cirrus, but looked almost like an auroral arch. 

 They were about 45° long, and reached from N.E. to W. 



July 5. — Lightning at 2 h 25 m . Needle of indicator 

 moved. Thunder at 2' 1 45 m , and rain at 2 h 48 m . 

 Lightning again at 22' 1 25 m . 



July 11.— Thunder heard at 16 h 15 m . Hail at 17 h l. r > m , 

 and fog came on for a short time at 17 u 20 m . Faint badly 

 defined corona at midnight. 



July 19. — Small fragment of rainbow seen at 17 h . 

 This is one of the very few occasions on which a rainbow 

 has been seen from Ben Nevis as yet. 



July 20.- — Very fine morning, with clear views. The 

 sea below dead calm — detached cumulus above other hill 

 tops. At 9 h the formation of this cumulus from fog rising 

 perpendicularly out of the valleys was noted. At 18 h rain 

 was seen to be falling at the moor of Rannoch. At 21 h 

 ugly heavy cumulus seen to the S.W., and at midnight 

 snow came on. 



July 26. — At 10 h solar halo observed, colours quite 

 distinct, red inside. Radius of red by stephanome. 



22° 45' 

 22° 30' 



Mean, 22° 54' 



(1st 

 )2d 

 13d 



1st measurement, 

 2d 



0' 

 20' 



Jti/y 27. — Fine all day ; 

 forming cumulus above hills. 



(ita 



fog rising from valleys, and 

 Sea below quite calm. 



