ON METEOROLOGICAL OBSERTATIONS ON BEN METIS. 



35 



The following are the yearly extremes of temperature since the 

 observatory was opened : — 



The niost noteworthy feature of these figures is the close approach the 

 annnal minima make to each other, the close agreement of the four and 

 the by no means low temperature they indicate in view of what occurs at 

 lower levels. This may be explained by the observatory being built on 

 the very top of the mountain, thus minimising the effects of terrestrial 

 radiation during the winter months. Previous to June 1887 the highest 

 temperature was 60°-l. But in that month this temperature was several 

 times exceeded, and on the 24th of the month the registering thermo- 

 meter recorded a maximum of 67°-0. The mean temperature of the 

 month was 45°4, or 'J°-2 higher than that of June 1886. The absolutely 

 lowest temperature was 31°-0, and of July following 30°-8. In these two 

 months, therefore, temperature fell but little below the freezino- point, 

 thus indicating for this height in the atmosphere a more prolonged period 

 of relatively high temperature tban has taken place since the observatory 

 was founded . 



The records of the simsbine recorder commenced in the end of January 

 1884. As regards the two complete years for which there are now obser- 

 vations, there were 680 hours in 1885 and 576 hours in 1886 beino- 16 

 and 14 per cent, of the possible sunshine of these years. From January 

 to July of the present year the percentage of possible sunshine has been 

 28, a result largely due to the comparatively large amount of sunshine in 

 April, May, and June, which amounted to 31 per cent, of the possible 

 sunshine. Up to May 31, 1887, the largest number of hours of sunshine 

 in any month was 162 in July 1885 ; but during last June there were 

 206 hours, or nearly 40 per cent, of the possible sunshine. In July 

 following there were only 58 hours of sunshine, being little qjore than a 

 fourth of the sunshine of June. The distribution of the sunshine durino- 

 the hours o Ithe day was similar to the results obtained for previous years' 

 as detailed in the Committee's report for last year. 



As respects the rain and snowfall, it is desirable to keep in mind that 

 some uncertainty will always necessarily attach to the recorded amounts 

 owing to the snow-drifts, the breaks that occur in the returns in con- 

 sequence, and the general uncertainty of the estimates formed for the 

 periods of these breaks. 



During 1885 the amount of the rainfall was 146"50 inches, beinf the 

 first whole year observed; but in 1886, the amount was only 10784 inches. 

 The amounts for the months of 1886 were, beginning with January in 

 inches :— 12-76, 2-84, 5-91; 4-59, 6-25, 7-60; 10-99, 10-16, 13-03 ■ 8-16 

 14-57, 10-98; and for 1887 to July inclusive, 17-80, 13-30, 5-90 '; 7-53' 

 3-97, 7-51 ; and 14-54. The number of days during 1886 on which the 

 precipitation was less than 0-01 inch were 97 days, and from January to 

 July 1887, 87 days. The largest monthly rainfall of these nineteen months 

 was, therefore, 17-80 in January 1887, and the smallest 284 inches in 



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