318 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



[1883-84. 



colours were more or less marked all day. Fog filled valleys, 

 an 1 lay over lower hills, though not in such a continuous 

 Bheet as yesterday. The sky continued clear all night ; 

 stars very bright, but temperature did not fall. At 

 ■20 li it rose from 28° to 32 u , and continued well above 

 freezing point all night. At 15 h sun sank into cloud 

 bank. 



Dec. 27. — At 7 h red streak round eastern horizon. 

 This gradually brightened, and turned to yellow just before 

 sunrise ; at the same time the sky near W. and S.W., 

 horizon being blue-green in colour. The hills near were 

 well seen, snow greatly melted off them. Before noon fog 

 and mist came on, which continued all afternoon. No 

 fresh snow having fallen for several days, the surface is 

 hard and firm — in many places compacted into ice by the 

 rain which fell at beginning of thaw. 



Dec. 28. — Barograph was found to have stopped at 

 1 l h on Dec. 27. Put on again at 2 h Dec. 28. Cause of 

 stoppage unknown. 



D ec . 29. At 16 h 40™ three-bulb thermometer put out, 



hanging exposed on nail at east side of posts on which box 

 was. 





- Small 

 Bulbs. 



Medium 

 Bulbs. 



Lavse 

 Bulbs. 



Humidity 

 (Saturation = 100). 



17* . 



18" . 

 19i> . 

 20 h . 



32° -2 

 32° -0 

 31°-9 



29°-9 



32° I 

 32°'0 

 31°-7 



29°-9 



32° '0 

 32° -0 

 31°-2 



29°-9 



100 

 100 

 100 

 100 



At 19 h the small bulb was coated with ice, the others 



Eed 

 Yellow 

 (Stratus) 

 Pale green 

 Cloud bank) 



were free. It was the one to windward. The instrument 

 was not examined again till 5 h on 30th, when it was found 

 to be thickly covered with snow crystals, and quite unread- 

 able. It was therefore taken in. Dry bulb temperature 

 at 5 h , 22°-l. 



Dec. 30. — Fine day, with wonderful 

 colour effects. At sunrise the zenith 

 sky was very blue. The sun rose from 

 cloud bank. About 3° above which was 

 a layer of dark stratus. Colours and 

 clouds as indicated in margin. To the N.E. sky at 

 horizon was a dirty-green colour. Sun shone brightly 

 all day, with curious reddish or copper colour under it, 

 increasing in intensity downwards to horizon. Max. 

 reading of black bulb in vacuo, 47 inches above snow, 

 73° - 8 at 13 h . Shade temperature at same time 19° '5. 

 Meteor seen at 20 h . Started from Orion, and went 

 downward at an angle of 70° to horizon to westward. 

 Clear starlight night ; very fine. 



Dec. 31. — At 7 h dark red streak round 

 eastern horizon for about 60°. At 8 h 

 colours as shown in margin. At 9 1 ' 

 colours disappearing. Sun shone all day ; 

 dull reddish colour round horizon under 

 colours at opposite azimuth. Sunset red, passing into 

 blue above S.S.E., sky copper colour. N.E. dark blue- 

 green, becoming at 16 h 30 m a yellowish-green. Above 

 sun after sunset, sky red, passing into blue, and that 

 into green still higher up. Above the green a curious 

 mauve tint. These colours gradually died out from 

 above. The moon was green, and continued so as long 

 as observed. Clear starlight night. 



15° Pale violet 

 7° Green 

 4° Yellow 

 Horizon 



it — greenish 



1884. 



j cnu 3. — At 7 h blood-red colour on eastern horizon, red 

 and green to E. at 8 h . Sunrise red ; very fine. Day 

 dull, but with green and copper coloured sky to north. 

 Southerly sky clouded and dark. .Wind was S.E., and it 

 was noticed, when fog blew up over the top from Glen 

 Nevis, that the wind lulled as the fog came up. Dark 

 clouds were hanging about all day, and in evening they 

 formed a canopy over hill, leaving horizon clear. At 17 h 

 35 m lunar halo. Radius 17° (V). Colour white, very faint. 



./,„;. 5._Very stormy. At 7 h 28 m wind southerly ; 

 blew lamp of observer out several times. This is the first 

 time this has happened. 



j an _ 6. — Everything covered with ice, either solid or 

 crystalline. At 4 1 ' thermometer box was frozen so fast that 

 it needed chisel to open it. Copper wire stays on stove 

 pipe grew to 4 inches diameter of solid ice. At 10 h some 

 snow-flakes about 1 inch diameter were observed. 



,/,,„. 7. — At 9 h there was more than an inch of solid ice 

 on thermometer box and on thermograph (tin) box. At 

 20 h mist and cloud driving over bill, fleeting coronas (red 

 outside) forming as they passed. 



Jan. 3 0.— 9th and 10th very stormy. At 14 u 35 m 

 indicator of telegraph instrument moved by earth current. 

 Corona seen about 20 h 20 m . 



Jan. 11. — Heavy drift all forenoon. Thermometer box 

 had to be cleared several times. 



Jan. 12. — Thermometer box shifted. Taken in after 

 noon observation. Max. and min. put out at 12 h 31 m . 

 But dry and wet were so hard frozen in that they could 

 not be got clear of the old box till 13 h , when they were 

 put out. At 19 h the bulbs of thermometers were 38 inches 

 above snow. At 21 h the box was covered with ice. 



Jan. 14. — This last two days everything has been 

 covered with ice ; the thermometer box needed to be 

 cleared several times, the ice being hacked off with a 

 chisel. The box taken in at noon on Jan. 12th took 

 about 40 hours to thaw, although it was standing in a 

 large pail about one yard from side of stove. 



Jan. 15. — Between midnight (Jan. 14) and l h lunar 

 corona seen. Distinct orange ring, 2° 30' radius ; inside 

 of which is the true corona, with blue next moon. 

 Outside orange ring a bluish-green space edged with red 

 or orange rim. This space did not look like a second 

 corona ; the colour was too uniform. Radius of outer red 

 ring 5°. This green in the outer ring strongly resembled 

 the green tints seen in the recent sunsets. Moon gave 

 usual continuous spectrum, but as the spectroscope was 

 moved aside, just after leaving the outer edge of all, a pale 

 lilac colour appeared at the green part of spectrum. At 

 14 h the moon was surrounded by a very faint corona en- 

 tirely blue. 



Jan. 16. — At 10 h put out sunshine recorder for first 



