76 



BEN NEVIS OBSERVATORY. — LOG-BOOK. 



[1888. 



shifting gradually to W. The rain to-day mostly fell in 

 heavy showers. 



Oct. 28.— A heavy shower of hail fell at about 16 u 30 m , 

 quite whitening the ground; hail fell again several times 

 later, and sleet at 23 1 ' and midnight. A flash of light- 

 ning, accompanied by a strong earth current in telegraph 

 cable, was observed at 18 h 33 m . The S.W. winds which 

 lasted np to about 17 h had the same squally character as 

 yesterday. 



Oct. 29. — Rather heavy snow showers fell during 

 the day, the snow being mostly hard and icy in character, 

 but at night, in the intervals between the showers, the sky 

 was sometimes cloudless. The windward {i.e., N. and W.) 

 louvres of thermometer box were choked with ice formed 

 out of the mist till 22 h , after which they were cleared. 

 A flash of lightning was seen at 19 h 8 m ; no thunder or 

 earth current. 



Oct. 30. — The snow which fell to-day was hard and 

 icy in texture, almost passing into hail at times. It did 

 not melt away, but lay covering the ground. From 7 h to 

 10 h inclusive the wet bulb read a few tenths, never over 

 half a degree, lower than the dry bulb, but as this was 

 obviously due to the wet bulb being frozen while the dry 

 was between 32° and 33°, these readings were discarded, 

 and the wet bulb entered on daily sheet as the same as the 

 dry bulb. 



Oct. 31. — The thick wetting mist to-day covered every- 

 thing with ice and the louvres of the thermometer box were 

 a good deal choked up. 



Nov. 1. — The thermometer box was shifted at 4 h 20 m . 



Nov. 2. — The hill top was clear of fog mostly all fore- 

 noon, and at times in afternoon. At 12 h a weasel was 

 seen at the Ordnance Cairn. At 5 h 30 m the thermometer 

 box was shifted. 



Nov. 4. — To-day and yesterday the fog cleared for a 

 little about midday, and a few minutes of sunshine were 

 recorded each day. Both days also snow crystals were 

 rapidly forming from the fog on all exposed surfaces, 

 though little or no snow was collected in the gauge. 



Nov. 5.— Fog crystals forming all day. At 18 h it was 

 observed that they were brown. 



Nov. 10. — Since the 4th the weather on the different 

 days has been very much the same, viz., gales from E., 

 E.S.E. or S.E. blowing with forces varying from 5 to 10, 

 fog on the summit almost continuously, from which fog 

 crystals were forming in abundance on the windward side 

 of obstacles, and little or no real snow falling. 1 



Nov. 15. — At 2 h the summit cleared, and till 6 h the 

 air was dry. At 2 h 15 m the thermometer box was shifted. 

 Top clear but dull, threatening pallium on sky from 22 h 

 till midnight. 



Nov. 16. — Very stormy till 10 h . The wind was very 

 squally. The observer was blown down several times. 



1 On the top of " M'Lean's Steep " and on the slope between that 

 and the "Second Gorge," holes in the snow-crust were observed to 

 leeward of cairns and large stones. The edge of each hole was a 

 thawing rim of ice, with no snow inside among the stones. Water 

 was dropping from the edge of the holes, but 2 or 3 inches away 

 the snow was quite dry and powdery, and the temperature of the 

 air was all the time below freezing, and on one day, the 6th, was 

 as low as 23°, i.e. at the Observatory. Quite different holes were 

 observed on "M'Lean's Steep" within 6 feet of the cliff's edge, 

 where spaces, 3 feet in diameter, were laid bare, and pieces of the 

 crust and small stones strewn about on the surface. 



St Elmo's Fire was seen at 6 h 5 m as glows 



From 5 h till ll h there was no raingauge out, the amount 

 of icy drift making its readings useless. At 8 h it was 

 observed that one of the cups (the mended one) of the 

 Robinson anemometer was gone, and could nowhere be 

 found, and also that the whole pillar on which the 

 instrument is mounted was shaking wildly. At 9 h it was 

 observed that another cup was gone, and the observer 

 attempted to stop the instrument but failed, owing to the 

 strength of the wind. The cups broke off with their arms 

 and stays attached to them. One has been found, but the 

 other has been blown over the cliff apparently. The 

 flexible shaft of the anemometer gave way at the middle 

 joint; apparently because of the rocking of the pillar. 

 All round the Observatory, stones (thin packing stones) 

 were blown out of the wall, and several of these were 

 found on the kitchen roof. Lightning was seen at 6 h 13 m 

 and again at 23 h 40 m ; at the latter hour the flash was 

 accompauied by a click in the telegraph instrument, and 

 followed in about 3 seconds by thunder, 



Nov. 17. 

 on lightning rod, vane, Kobinson's anemometer, and on 

 kitchen chimney. Hissing noise heard. It disappeared 

 in about 3 m after it was first observed. Several times 

 during the forenoon the telegraph instrument was disturbed 

 by lightning or earth currents. Conical (and spherical), 

 snow was falling about midday. At 23 h a weasel was 

 seen in the visitors' room. It was larger than the common 

 weasel and was almost pure white in colour. 



Nov. 19. — Very heavy rain was falling all morning. 

 For the hour ending 12 h , 0'373 inch was measured. 

 There was a sudden drop in the temperature between 12 h 

 and 13 h , the readings at these hours being respectively, 

 37°-4 and 31°-9. The summit was clear at 22 u and 23 h , 

 but the sky remained heavily overcast, and to N. at 22 h 

 the appearance was very " gloomy." 



Nov. 20. — Bright flash of lightning seen at l h 45 m , and 

 another at 18 h 35 m . Former followed by thunder and a 

 heavy squall of wind. St Elmo's Fire was seen at 19 h 15 m for 

 10 m , faintly, on kitchen chimney. Hissing noise. 



Nov. 22. — Thermometer box was shifted at l h 15 m . 

 Very heavy rain was falling till 1 4 h ; the amount measured 

 for the hour ending 8 h was 0*430 inch. 



Nov. 24. — Very heavy rain falling in early morning, 

 the amount measured for the hour ending 2 a.m. being 

 0'373 inch. Snow fell in afternoon, and heavy rain again 

 from 20 11 till midnight. 



Nov. 25. — Thunder was heard at 15 h 45 m , and two 

 clicks were heard on telegraph instrument during the 

 hour 15 h -16 h , and another at 16 h 20 m . The top was 

 clear at 23 h and at midnight. 



Nov. 26. — The top remained clear till 2 h , but thereafter 

 it was covered with fog, except at ll h and 12 h , till 18 h 

 when it cleared again ; and till midnight the sky was 

 cloudless or almost so, and (from 19 h ) the air was very 

 dry. The thermometer box was shifted at 1 9 h 20 m . 



Nov. 27.— The top was clear till 4 h . At h 7 m a dark 

 cir.-str. cloud was observed low to S.W., which gradually 

 spread, causing an overcast sky at l h , 2 h and 3 h , but 

 breaking up before the fog came on. At 4 h a lunar halo 

 was seen. At 14 h the fog crystals of to-day's formation 

 were 3 to 4 inches long. 



Nov. 28. — The top cleared at l h , and remained clear till 

 17 h , but was covered after this. A lunar halo was seen 



