552 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



[1903. 



May 11. — Lunar coronse seen at l h and 2 h . Ther- 

 mometer box changed after 5 h . 



May 12. — Thermometer box changed after 4 h . 



May 16. — St Elmo's Fire seen at l h . 



May 17.— Summit clear from 10 h till 14 h . Sky 

 cloudy, and a great deal of fog hanging about bills 

 around. Thermometer box changod after 10 h . The 

 depth of snow has increased a good deal during the last 

 two or three days, and has now reached 125 inches. This 

 is the greatest depth measured at Post A. since 1894. 



May 18. — The fog on summit sank below after ll h , 

 and soon after broke up and disappeared altogether. 

 Sky cloudy in afternoon, but cloudless after 21 h . Air 

 dry after 12 h , and very clear, the Outer Hebrides being 

 distinctly seen all the afternoon. Thermometer box 

 changed after 7 h . Height above snow 47 inches. 



May 19. — Summit clear all day, except from 7 h till 

 10 h , when there was fog rising in Glen Nevis and 

 enveloping hill-top at intervals. The sky during the 

 day was cloudy with cum., but up till 6 h , and again after 

 18 h , it was cloudless. Haze in valleys all day. 



May 20. — Sky cloudy, with cir.-c. and cir.-s. moving 

 slowly from S.W. till 5 b . Fog or mist since. Pretty 

 thick haze all round in early morning. Low lying fog 

 to N.E. at 4 h ; at 5 h it had spread round to N. 



May 23. — Summit clear for a few hours in after- 

 noon, and air slightly dry. Sky cloudy or overcast and 

 thick fog round about. Slight showers of snow in 

 afternoon. 



May 24. — Temperature low in morning, but it rose 

 quickly to 41°-3 at 14 h , that being the highest observed 

 reading this year. The air has been very dry at times, 

 the lowest humidity being 44 at midnight. Sky cloudy 

 most of the day, with cir.-c. chiefly, moving moderately 

 fast from the S.W. At 4 h some hard packed cir.-s. above 

 horizon to N.E. and E. Haze around all day, becoming 

 thicker in afternoon. 



May 25. — Cloudy or overcast sky till 13 h , sky cloud- 

 less since. Thick hare high up all round. 



May 27. — Haze high up all round, thickest in fore- 

 noon. Fore-glow colours in morning. Thermometer 

 box lowered one step on ladder at h 12 m . Height 

 above snow 40 inches. 



May 28. — Sky cloudy during the day, with cirrus 

 chiefly. Haze cleared away in early morning, and 

 atmosphere was pretty clear during day. 



May 29. — Sky somewhat cloudy all day. Fog in 

 valleys to N. and N.E. in early morning, and again 

 forming to N. after 19 h . 



May 30. — Fog in valleys to N. and N.E. in early 

 morning, but dispersing after 9 h . Sky almost overcast 

 all day. Fog on hills in afternoon and at times passing 

 over summit, and finally settling on hill-top after 21 h . 



May 31. — The mist sank below summit after 21 h 

 leaving sky almost cloudless. Thermometer box lowered 

 one step on ladder at h 10 m . Height of bulbs above 

 snow 39 inches. 



June 3. — Sky almost cloudless till 10 h ; cloudy till 20 h , 

 mist since. Very hazy all round in morning, but clearing 

 away in afternoon. Ascending currents in Glen Nevis 

 and in N. cliff at 17 h and 18 h . 



June 4. — Air very dry and clear during part of the 

 day ; lowest humidity 37 at 8 h . Mist till 6\ and again 



after 19 h , with heavy rain. Detached fog in valleys and 

 on hills. Ascending currents in Glen Nevis and in N. 

 cliff at 18 h . 



June 5. — Summit clear, but fog in valleys and on hills 

 all afternoon. 



June 6. — Sky cloudless down to horizon all day. Fog 

 in valleys chiefly to W. till 10 u . No fog since. Air 

 very dry in morning, the lowest humidity 31 at l h and 5 h . 



June 7. — Sky slightly cloudy most of the day. Fog 

 in valleys in early morning, but disappearing after 7 h . 

 Haze during forenoon, but clearing away in afternoon. 



June 8. — In the forenoon there were no lower clouds, 

 but fog lay in the valleys till 10 h ; in the afternoon 

 lower clouds formed in the sky. 



June 9. — Fog in valleys in morning. 



June 10.— Sky overcast most of the day, the clouds 

 being very low, and occasionally enveloping the summit. 

 At 23 h the sky became cloudless, the fog having fallen 

 into the valleys. 



June 11. — Sky practically cloudless, but fog lying in 

 the valleys in the morning, which dispersed towards mid- 

 day ; in the evening fog was forming on the hills at 

 N. horizon. 



June 12. — Sky cloudy, fog lying in the valleys all 

 forenoon. 



June 14. — The thermometers were changed after 7 h , 

 and again after I7 h . 



June 15. — Sky cloudy, and fog lying in the valleys 

 most of the day. 



June 16. — Sky very cloudy and fog below all day. 



June 17. — Sky cloudy in the morning, with fog below 

 all round. At 10' 1 the fog rose, and during the remainder 

 of the day the summit was in fog or mist. 



June 19. — Fog in early morning, but summit clear 

 from 7 h onwards, with fog below. 



June 20. — Sky cloudless in the morning. There 

 was no fog below all day except at 19 h , when loose 

 fog was rising from the N. cliff and passing over the 

 summit. 



June 22. —At 14 h two birds thought to be eagles were 

 seen to the N.E. from the summit. 



June 26. — After 5 h the thermometer box was lowered 

 one step on the ladder. 



June 29. — Earth currents in telegraph cable noted, and 

 thunder heard from 2 h till 7 h 20 m . Lightning also seen 

 at 6 h 58 m and 7 h 6 m . 



July 1. — After 12 h the thermometers were transferred 

 from the winter into the summer box. 



July 2.— Thunder heard and lightning seen at 22 h 27 m 

 and 22 h 35 m ; earth currents also noted. 



July 14. — The air during the day was very clear, and 

 for nine hours the maximum visibility was observed. 



July 18. — During the forenoon the sky was partly 

 covered with cumulus and cirrus, but from 12 h onwards 

 it was nearly cloudless. The air during the day was very 

 clear. A thin haze lay in the valleys most of the evening. 

 A solar halo was noted at 14 h . 



July 19. — Fog lying over the hills to N. and E. in the 

 forenoon. At 22 u detached fog lay over all the surround- 

 ing hills, and the haze in the valleys was very thick. 



July 20. — From 18 h till midnight the sky was 

 absolutely cloudless. The haze was very thick all round 

 during the evening. 



