1884.] 



BEN NEVIS OBSERVATORY. — LOO-BOOK. 



321 



top of Ben Nevis. Top in fog from ll h to 15 h . At 23 h 

 heavy cumulus fog all round, and red glare under moon. 

 At 17 h 20 m an earth current moved needle of A B C 

 telegraph indicator six letters on dial. 



April 13. — At 4 h lunar corona observed, very misty 

 looking, with red ring inside an outer green one. Cumulus 

 cloud, and fog round horizon all day. 



April 14. — Heavy dark clouds, and fog round horizon 

 all day. 



April 15. — Dark cumulus round horizon all day. 



April 17 '.■ — Stratus and cumulus hanging about horizon 

 all day. Sunset very fine, showing all the spectroscopic 

 gradations of colour. At 22 h a magnificent aurora was 

 observed. It formed a double arch of light, with dark 

 space under it. At 22 b 5 m streamers were shooting up- 

 wards from all parts of both arches, and at 22 11 12 m the two 

 disolved into one broad, badly defined arch. The centre 

 of the upper arch was about 20° above horizon, and 

 of the lower arch 10°. The upper extended from W.N. W. 

 to E.N.E., and the lower from N.W. to N.E. After 

 20 h 15 m the aurora consisted mainly of horizontal waves 

 of light, rolling upwards to nearly the zenith, and appar- 

 ently converging there. Mingled with these waves were 

 long rays, shooting upwards towards the zenith, and reach- 

 ing to within about 15° of it. By midnight it had dis- 

 appeared; but the upper edges of the clouds on northern 

 horizon were still luminous. No definite reflection of the 

 aurora in any of the lochs was observed, and no spectro- 

 scopic observations were made on it. A meteor was seen 

 near zeuith at 22 u 20 m . Quiet, fine, but rather dull 

 weather followed for the next few days. 



April 21. — At 8 h with light fog overcast sky, and 

 temperature of 25 0- 8, small soft crystals of snow fell ; 

 dead calm at the time. 



April 23. — Grey crystals of snow forming; some an 

 inch and half long. 



April 24.- — From 22 h to midnight a luminous appear- 

 ance in sky and clouds, especially to N.E. 



April 25. — At l h a faint aurora seen ; no arch visible, 

 but streamers, very bright at times, were observed rising 

 to a height of about 30°. At 2 h faint glimpses of the 

 aurora were seen through fog. At 3 h neither arch nor 

 streamers were seen, but spasmodic flashes of light rose, 

 apparently from quite close at hand in the fog towards the 

 zenith. At 3 h 5 m fog cleared off, and a cone of light with 

 its base along horizon from N.N.E. to E.S.E., and its vertex 

 5° east of Cassiopeia was seen. At 4 h the cone was larger, 

 reaching to within 20° of zenith. The needle of A B C 

 telegraph instrument was moved on three letters by an 

 earth current at 3 L 5 m . At 3 h 5 m bright meteor seen. 

 Started at 30° elevation, bearing E. and S., and fell verti- 

 cally downwards. 



April 28. — At 3 h triangular patch of sky rising from 

 N.E. horizon as far as Cassiopeia, of a milky aspect. Very 

 few clouds at the time. Sun did not rise till after 4 h . 



April 30. — At l h doorway was almost choked with 

 drifted snow. At 10 h 30 m a heavy shower of very large 

 hail fell. 



May 3. — At midnight brilliant lunar 

 corona observed ; colours as in margin. It 

 disappeared suddenly at h 5 m , before there 

 was time to take any measurements. 



May 4. — The hills round Ben Nevis were seen to be 

 covered with fresh snow for a great part of their height. 



Bed 



Green 



Reddish 



Yellow 



D 



At 14 h 45 m heavy hailstorm with thunder. The needle 

 of A B C telegraph indicator moved on three letters. 



May 6. — Box shifted after noon observation. Badly 

 defined lunar corona seen at midnight. Radius of red ring 

 3° 45' ; of blue 2°. 



May 7. — At 8 h a solar halo observed, red inside, bluish 

 colour outside. Fog was passing at the time, and when it 

 came on, the halo disappeared; but a corona was seen 

 formed on the fog. At noon snow came on and drifted 

 heavily. At 15 h the doorway was blocked at the upper 

 end, and no temperature observation was taken then or at 

 1G U ; but at 17 h a hole was made vertically upwards. By 

 this means the observations were continued, the hole being 

 covered, when not in use, by sacking and boards to keep out 

 drift. 



May 11. — Sular halo observed at 10 h . Well defined; 

 red inside. Radius by stephanome 22° 30'. Thermometer 

 box shifted at 19 h . 



May 13. — Faint solar halo, red inside, at 10' 1- 



May 18. — At 20 h thermometer box was covered with 

 feathery snow crystals, particularly on the upper edge at 

 the west side. 



May 19. — At 9 h huge masses of cumulus cloud above 

 southern hills. At 14 h 30 m thermometer box shifted. 



May 22. — In the afternoon a tourist with a horse 

 visited the observatory. This was the first horse up this 

 year. 



May 23. — At ll h the higher clouds to northward were 

 observed to be whirling round and getting torn to bits. 

 At 13 b solar halo observed. Radius about 20°. Colours 

 very brilliant, red inside, blue outside, yellowish in centre. 

 Horizon hazy, with cumulus above it all day. A robin 

 redbreast seen, singing near the second gorge, from observa- 

 tory in afternoon. At 19 1 ' the N.W. horizon was brownish- 

 yellow in colour; and the sea near the Isle of Bum fiery 

 red. 



May 24. — Very fine; sky almost cloudless, but thick 

 haze all round horizon. Before sunrise and after sunset 

 a dense fog filled the valleys among the more distant hills 

 to north and east. 



May 25. — Very fine; but more fog hanging about the 

 surrounding hills than yesterday. Green 



May 27. — At 3 h the north-eastern sky Yellow 

 was coloured as in margin. Atl0 h agreen Red 

 belt was seen above the horizon from Haze 

 S.W. to N.W., with dark objects appearing and disappear- 

 ing in it. Hardly any snow to be seen, except on Ben 

 Nevis, on the flat-topped hill to the eastward, and on the 

 Cairngorms. 



May 28. — A level sheet of fog filled all the northern 

 valleys, coming as far south as the head of Loch Lochy, 

 from 3 h to 9 h . 



May 29. — At 9 h the large bulb of black bulb was 

 covered with a film of moisture to windward. The read- 

 ings of dry and wet were 39'7 and 39"1 ; clouds were 

 passing overhead, almost touching the hill. 



June 3. — Solar corona at 9 h 5 m . Red inside, blue 

 outside. After 15 h the thermometer box was removed from 

 ladder and placed on wooden stand, 13 inches above snow, 

 while the upper joint of the ladder was taken off. At 16 h 

 a fresh box was fixed on remaining part of ladder, 45 

 inches above snow. At ll h the sky was overcast with 

 stratus, and the clouds were observed to be thinner just 

 above the top of Ben Nevis than elsewhere. 



