1886.] 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



341 



tained large isolated drops of water both yesterday and 

 to-day. 



Oct. 6. — At about 18 h the hill top cleared, leaving fog 

 over the lower hills and rather high clouds of cumulus 

 type above. Thunder was heard at 17 h 45 m , and distant 

 thunder and lightning at 18 h 5 m , 18 u 16 m , and several 

 times about 21 h . At 19 h lightning was seen in the 

 distance to S.S.E. low down just above the fog. At 21 h 

 38 m a flash was seen, followed closely by thunder. At the 

 time of the flash a sharp crack was heard in the tower 

 stove-pipe, as if a discharge had gone down the lightning 

 rod. Another flash, with a similar crack and followed 

 closely by thunder, occurred at 21 h 47 m . From 21 h 40™ 

 to 21 h 47 m rain fell heavily, and the top was enveloped 

 in thick mist. No thunder or lightning was observed 

 between the flash at 21 h 38 ra and that at 21 h 47 m , and 

 none after the latter ; during that time the thunder-cloud 

 seems to have been resting on, or crossing over, the hill 

 top. No damage was done to the Observatory. 



Oct. 7. — At 12 h a solar fog-bow was observed. No 

 colours, only a broad white band. Radius to inside of 

 bow, 36° 20' • outside, 43° 36'. This afternoon the 

 Robinson anemometer was taken down. 



Oct. 10. — The ground to-day got all covered with dry 

 snow about 2 inches deep. 



Oct. 14. — At 23 h misty lunar corona. Double ring, 

 outer, blue inside the red, and inner yellowish. Size 

 varying rapidly, brightest when largest. Radius of inner 

 red, when of medium size, 2° 26'. 



Oct. 17. — The snow which fell early this morning was 

 in large soft flakes, and was not hard and dry like the 

 last. 



Oct. 18. — To-day and yesterday evening the ground was 

 all icy. Louvres of thermometer box badly choked at 

 night, especially to windward. 



Oct. 20. — At 10 h the time error of the Observatory clock 

 was found to be + 5 m 5 s . It had been supposed to be only 

 + l m 30 s . The times since the 1 6th have therefore probably 

 a gradually increasing error, but no correction has been 

 applied to any readings. 



Oct. 21. — The fog or scud cleared overhead occasionally 

 at 17 h and 18 h , showing blue sky with some cirrus. 



Oct. 22. — Fog-bow seen at ll h 25 m ; colours as in fig. 

 8. The order of colours in the glory was not determined. 

 No measurement was got. The pink was a badly defined 

 space, not a true band. Auroral streamers seen at 21 h ; 

 the arch appeared to be just about the horizon. Thick 

 haze in the valleys and over the other hills at night. 



Oct. 23. — Low fog over lochs in Caledonian canal valley 

 at 8 h . 



Oct. 24. — White icy fog crystals forming at night. 



Oct. 25. — At 16 h glory seen on fog to north-eastward. 

 Rather misty and badly defined; four rings, inner one a 

 mere blotch ; second, yellow and red — the brightest of the 

 four ; third, green and red ; fourth only red seen clearly. 

 The third and fourth were only seen occasionally. Radius 

 of first red, 1° 10' (bad observation) ; second red, 3° 46' ; 

 third red, 6° 18'; fourth red, 7° 22'; yellow in second 

 ring, 2° 55' ; green in third ring, 4° 31'. 



Oct. 26.— Meteorite seen at 20 u 2 m ; started at about 

 60° altitude to the E. by S., and fell almost vertically. 



Oct. 28.— At 15 h 7 m dry and wet bulbs were shifted. 



Nov. 2. — At 4 h 5 m St Elmo's fire seen on lightning con- 

 ductor, anemometers, and kitchen chimney. The brushes 



of light were broad-looking and bright. Hard dry snow 

 was falling at the time. 



Nov. 5. — At 18 h lunar corona seen; colours as in margin 

 (outer blue probably a margin). Radius of Blue 

 red 2° 17' and of blue 4° 43'. Well-defined Red 

 halo seen all evening. The two following !> 



measurements were taken: — At 19 h , radius, 22° 36'; at 

 20 h , 22° 0'. Fleeting corona also seen ; colours as in 

 margin. At 19 h a light was seen to north- Eed 

 ward, possibly auroral. Heavy drift at Blue 

 night, making rain-gauges useless, but Red 

 apparently no snow fell. 1) 



Nov. 6. — Very squally all morning, with strong back 

 swirls in the wind. No gauge was out till 19 h , but pro- 

 bably no snow fell. At 14 h the thermometers in the large 

 thermometer box were taken in. 



Nov. 7. — At ll h , though the temperature was 21°, 

 minute drops of rain were falling. Thermometer box 

 shifted at 12 h 25 m . 



Nov. 8. — One of the Observatory horses was up for the 

 last time this year. 



Nov. 9. — The fog crystals forming to-day were slightly 

 brown in colour. Thermometer box shifted at 15 h 15 m . 

 Fleeting misty double lunar corona, yellow inside and 

 blue outside, seen at 21 h . Great masses of cumulus fog 

 all round at night, and also over the southern hills. 



Nov. 11. — At 8 h the shadow of Ben Nevis was seen on 

 low clouds to N.W. and with it a badly-defined glory. A, 

 portion of a solar halo was observed at 10 h and also at ll h ; 

 red inside. At 14 h the western hills were topped with a 

 sheet of fog reaching from about 2000 to 5000 feet in 

 height, and extending from Mull to the extreme north. 

 This rolled on and reached Ben Nevis at about 15 h . Ther- 

 mometer box shifted at 8 h 10 m . 



Nov. 12.— Box shifted at ll h 30 m . Double fog-bow 

 seen at 13 h ; outer bow white, inner bow red and blue, 

 red being inside. Faint single fog-bow Eed 

 (white) seen at 14 h . Lunar fog-bow and Green 

 misty corona at 18 h . Triple corona at 19 1 ' ; Blue 

 colours as in margin. Radius of red, 1° ^ e ^ 

 2J'; middle red, 2° 29'; middle green, 2° 3'. JJ 1 ™ 

 Size varying. Measurements were stopped Blue 

 by ice crystals from passing mist clogging Bed 

 stephanome. White fog-bow seen at same 

 hour. Portion of halo seen at 21 h ; radius, 

 21° 13'. Thin gauzy fog or mist filling valleys up to 

 the level of top of Ben, and hiding hills round all night. 



Nov. 13. — Fog similar to last night till 5 h , after which 

 it rose and covered the hill top. The drizzling rain covered 

 all exposed surfaces with ice. 



Nov. 14. — Thermometer box shifted at Bed 

 h 15 m . Meteor seen at 5 h 10 m . Triple Green 

 lunar corona seen at 5 h ; colours as in Blue 

 margin. Radius of inner red, 1° 23^' ; green 

 middle red, 2° 52'; outer red; 3° 36'; B j ue 

 inner blue, 1° 34|'. At 7 h red, green, and Bed 

 blue sunrise colours in eastern sky. At White 

 10 b sky at north-eastern horizon sickly P 



green in colour ; gloomy to N.W. 



Nov. 16. — Fog-bow seen at ll h , red outside and white 

 inside. A fainter bow was seen inside this one at times. 



Nov. 17. — At 10 h the snow that was falling consisted 

 of very small needle-shaped crystals. 



Nov. 18.— Thermometer box shifted at 4 h 20 m . Meteor 



White 



D 



