1892.J 



BEN NEVIS OBSERVATORY. — INSTRUMENTS, ETC. 



419 



The Telegraph Instrument has worked well throughout 

 the year. Daily weather reports from both stations 

 continue to be sent to the daily papers. 



Since September 8th Mr A. J. Herbertson has been 

 conducting experiments on the Hygrometry of the Air 

 on Summit. Since October 6 th he has been assistant 

 observer at the Observatory. 



In August Mr Edward Whymper made some experi- 

 ments on the behaviour of aneroids with varying pressures 

 at both stations. 



The Seismograph was not used during the year. In 

 September it was sent away to be repaired and tested, 



with a view to its being erected at the Low Level 

 Observatory. 



The Staff of the Observatory consists of R. T. Omond, 

 Angus Rankin, James Miller, and Samuel Weir. George 

 Robertson was on the staff till July 6th when his place 

 was taken by Weir. Mr John Crerar was telegraph clerk 

 in summer, and Messrs J. I. Craig, H. F. Rankin, 

 C. Stewart, A. J. Herbertson, and W. Stewart, took 

 the place of various members of the staff during the 

 holiday season. 



The Observatory Buildings are, and have been during 

 the year in fairly good condition. 



DEPTH OF SNOW 



Inches. 



This table gives the depth in inches of the snow lying on the summit of Ben Nevis on 

 the 1st and 15th of each month from the opening of the Observatory in 1883 to 15th July 

 1893, and also the maximum depth observed each year with the date of occurrence. During 

 the first winter, 1883-84, the depth was measured at the Thermometer Stand 12 yards from 

 the nearest part of the Observatory buildings, but for the rest of the time on a post standing 

 near the centre of the flat part of the hill top, over 20 yards from any obstruction. It was 

 selected as the position most free from accumulations of drifted snow, and therefore as a 

 place showing the results of the snowfall influenced only by melting, evaporation, and loss 

 from wind blowing away loose snow. During each winter drifts gathered to much greater 

 depths in more sheltered parts of the hill top. The entries on Nov. 1st and 15th, and on 

 Dec. 1st 1883, are approximate only. 





Oct. 



Nov. Dec. 



Jan. 



Feb. 



Mar. 



Apr. 



May 



June 



July 



Maxi- 

 mum. 



Date. 





15 



1 



15 



1 



15 



1 



15 



1 



15 



1 



15 



1 



15 



1 



15 



120 



134 



92 



51 



64 



70 

 36 

 52 



61-9 



1 



80 

 124 

 94 

 15 

 36 



26 

 30 

 30 



43-5 



15 



1 



15 



1883 

 1884 

 1885 

 1886 

 1887 



1888 

 1889 

 1890 

 1891 

 1892 



Mean 



31 



7 



23 



6-1 



[20] 

 34 



20 

 7-4 



[40] 

 23 



22 



8 



9-3 



[60] 



5 



32 



18 



14 



3 



8 



28 



14 



18-2 



80 

 33 

 44 

 13 

 46 



7 

 11 



9 

 41 

 27 



31-1 



70 

 46 

 44 

 43 

 52 



21 

 23 

 13 

 50 

 25 



38-7 



80 

 57 

 54 

 46 

 46 



33 

 24 

 10 

 52 

 26 



42-8 



107 

 66 

 85 

 35 

 43 



37 

 65 

 42 

 57 

 41 



57-8 



105 



122 



86 



39 



52 



44 

 66 

 38 

 68 

 54 



67-4 



114 



119 



85 



44 



48 



44 

 69 

 35 

 69 



58 



68-5 



114 



122 



92 



44 



56 



50 

 69 

 44 

 70 

 62 



72-3 



113 



136 



85 



50 



56 



47 

 82 

 54 

 66 

 60 



74-9 



105 



135 



122 



49 



61 



51 

 88 

 56 

 57 

 55 



77-9 



117 



128 



104 



67 



67 



53 

 92 

 58 

 64 

 34 



78-4 



55 

 87 

 63 



23 

 22-8 



3 

 55 



30 



8-8 



7 

 0-7 



141 



142 



123 



69 



71 



57 

 96 

 59 



74 

 66 



89-8 



May 8 



April 3 



„ 10 



„ 28 



May 6 



AprU 24 



., 25 



May 4 



March 9 



,. 17 



April 16 



1884 

 1885 

 1886 

 1887 

 1888 



1889 

 1890 

 1891 

 1892 

 1893 



Mean 



