NATURE 



{Jan. 3, 1884 



stove which heats the whole observatory, and on which 

 the snow melting and all the cooking is done by John 

 Duncan, the second assistant obser>'er and housemaid. 

 (In one of the walls is the combined sideboard and 

 crockery and instrument cupboard; against another stands 

 a small bench with a vice ; and on a third is the telegraph 

 instrument, Mr. tunond's desk and book-case, and the 

 drawers in which are kept the records of the observatory. 

 Out of the sitting-room open the three bedrooms for the 

 observers, which resemble very closely the cabins on 

 board a ship ; indeed the whole establishment has an 

 intensely nautical air about it, and the visitor steadies 

 himself instinctively now and then, and wonders that the 

 roll never comes. 



The rest of the building is occupied with a coal 

 and oil store, and a storeroom in which are kept the 

 cabin biscuits, dried potatoes, tinned soups, meat, and 

 vegetables, lime juice, and medicine chest ; which Mr. 

 Omond calculates will support the three observers till 

 June. 



The afternoon and evening we spent in watching the 

 observers at work, in dining (which we did very comfort- 

 ably off the Christmas cheer, viz. roast turkey and plum 

 pudding, provided for the inhabitants of Ben Nevis by a 

 thoughtful friend), and in eager discussion of plans for 

 the present and future work of the Observatory. The 

 routine of the observatory at present consists in hourly 

 observations of the barometer, protected thermometers, 

 dry and wet bulb and ma.ximum and minimum, wind- 

 direction and pressure, rain, snow, sleet or hail, mist, fog 

 or haze, clouds lower and upper, amount, species, and 

 direction, sunshine recorder, miscellaneous, thunder, 

 lightning, haloes, auror;e, meteors, &c., nature and pre- 

 cise time of occurrence of. The self-registering baro- 

 graph and thermograph now added to the collection of 

 instruments are working very well, and will be invaluable 

 for the record of sudden changes. The protected thermo- 

 meters and the thermograph are attached to a ladder 

 fixed in the snow. As the level of the snow rises and 

 falls, they are moved from step to step, so as to keep 

 them as nearly as possible to the regulation distance of 

 four feet from the surfae. A measurement from the top 

 of the ladder to the surface gives the depth of the snow, 

 which at present varies from six to ten feet at different 

 parts of the summit of the mountain. 



Any detailed account of the winter climate of Ben 

 Nevis would be premature and out of place in this notice ; 

 but Mr. Buchan has kindly furnished me with an analysis 

 of the meteorological phenomena on Christmas and the 

 following day which were in several respects remarkable. 



At I A.M. of Christmas day, temperature was 37^ o 

 from which it steadily fell to 3i°-5 at 11 a.m., the air all 

 the time being quite saturated and loaded with dark, gloomy 

 mist, with a barometer steadily rising. The wind was 

 moderate from north-west till 3 .'V.M., when it changed to 

 west-south-west. About noon the mist pall cleared 

 away and the sun shone out with great splendour. P'rom 

 this hour to miinight, the following most remarkable 

 observations were made (see table). 



Except a few cirrus clouds which appeared about one, 

 three, four, and ten o'clock, the sky was cloudless 

 throughout, and during the evening the stars sparkled 

 with unwonted brightness in the dark blue sky. 



These remarkable atmospheric conditions were strictly 

 confined to the higher region of Ben Xevis. Fog or cloud 

 covered the lower hills and filled the valleys all the after- 

 noon ; it rose sometimes as high as the " plateau of 

 storms," but was mostly below 3000 feet on Ben Nevis, 

 and d.ring the time no other hill showed itself through 

 the sea of cloud. The sunset of the ;5th, as well as the 

 sunrise of the 26th, was very beautiful. On the 26th 

 pressure remained high and steady, win! south-westerly, 

 sky generally clear, and temperature and humidity equally 



remarkable as on the preceding day. Indeed at 2 p.m. the 

 relative humidity, which was lower than could be calculated 

 from Glaisher's Tables, was only 34. At 3 p.m. tempera- 

 ture had fallen 6'9, humidity risen to 96', and a light 

 fog prevailed for the next four hours, the wind having 

 shifted from south-west to west-north-west. About 7 p.m. 

 the sky again cleared, temperature steady, rose from 28"''o 

 to 36-0 at midnight, and a humidity as low as 67 was 

 observed. The great significance of these ob?ervations on 

 Ben Nevis will be more apparent when comj ared with the 

 anticyclone which overspread so large a part of north- 

 western Europe at the time, to which, bein,,' situated on 

 its west side, we owed the mild weather of Chnstmas, 1883. 



In addition to the hourly observations, the observers 

 have had for some time back to conduct a constant war- 

 fare with the rapidi) -accumulating snow. Every now 

 and then all hands hid to be turned out to clear the 

 doors and windows of the observatory ; and it sometimes 

 happened that, when they went out for this purpose, the 

 snow drifted in so rapidly that it was almost impossible 

 to shut the door again. The device of the snow staircase 

 got over the difficulty to a large e.xtent as regards the 

 door, and it is proposed to build tubes with short lengths 

 of rectangular wooden framework, passing from the 

 windows up to the surface of the snow. .At the upper 

 end of these will be placed, at night or during heavy 

 snowfalls, light canvas doors, which can be afterwards 

 removed and additional lengths of framework added 

 according to necessity. The chimney will be lengthened 

 in a similar way by means of iron tubes, which have 

 been sent up for the purpose In this way the difficulties 

 of the present winter will be met. For the future it is 

 proposed to get over the difficulty of the accumulating 

 snow by building an observing tower at some little dis- 

 tance from the living-rooms. In this tower there will be 

 several stories with doors to the four cardinal [ oints of 

 the compass, so that the observers may use for exit and 

 entrance that story which is nearcbt the snow level, 

 and that door which happens to be on the lee-side 

 of the tower. In the ground-floor of this to«er it is pro- 

 posed to place a seismometer and self-registering mag- 

 netic instruments. On the roof will be placed an 

 anemometer for measuring the direction and strength of 

 the wind. It is proposed so to arrange this instrument 

 that its indications can be read inside the tower. This 

 appears to be essential, for during the storm on the 12th 

 ult. it was found impossible to go outside the observa- 

 tory, so that wind observations are wanting in the daily 

 sheet on that very interesting occasion. The observing- 

 tovver will be connected with the rest of the buildmgs by 

 a covered way of some length fitted with doors to cut oflf 

 the hot air ; and in all probability the accommodation of 

 the observatory will be increased by the addition of an 

 office, or experimenting room, and one or more small 



