700 MR ROBERT COCKBURN MOSSMAN ON 



referred to above tliere is little sunshine, which accounts for the comparatively small 

 diurnal range in the temperature values. The month closes with a low barometer, 

 gales now showing an increase. 



October. 



Pressure is low throughout, rainfall being well above the mean during the first 

 three weeks, with the exception of a few days about the 16th. Gales show an increase 

 after the 7th and are at a maximum about the 20th. This period is noteworthy as 

 having more rainy days than any other time of the year, although the downpours are 

 not of such a torrential character as in July and August. The winds during the month 

 present few features of interest, although a number of small and unimportant oscillations 

 take place from time to time. The excess of N. and S.E. winds is perhaps the most 

 interesting, the latter in connection with the increased frequency of gales. At the 

 close of the month pressure rises slightly, the rainfall diminishing about the time. 

 Temperature falls steadily throughout with few and unimportant interruptions. 



November. 



During the first week pressure is below the mean, but is well above it in the follow- 

 ing week. During the period of relatively high barometer, temperature falls quickly 

 with a considerable augmentation in the precipitation. Northerly winds show a 

 marked excess, a point of interest in connection with the rapid fall of temperature. 

 There is a good deal of sunshine till about the 10th, when the polar current asserts 

 itself. Gales become frequent about the 16th, when there is an increased tendency 

 for snow. The most pronounced feature of the meteorology of the month is the great 

 and rapid fall of pressure to a minimum on the 26th (see page 685), this being 

 accompanied by an increase in equatorial winds, in consequence of which the autumnal 

 fall of temperature is retarded. 



December. 



Pressure is below the mean in December during the first three weeks, temperature 

 remaining steady till the 17th. The cause of this interruption in the regular autumnal 

 fall of temperature is to be found in the increased prevalence first of S.E., then 

 of S., and finally of westerly winds. Gales during this time are frequent, while snow 

 is of uncommon occurrence. After the 1 7th temperature falls, S.W. winds 

 blowing with diminished frequency. Snow now becomes frequent, while pressure is 

 higher than during any time in the three months before or after. Calms are common 

 at this time, pressure being high, conditions eminently favourable for the deposition 

 of aqueous vapour on the dust particles and its consequent condensation into fog. 

 The increase of S.E. winds at the close of the year is of interest in connection 

 with the low temperature at the time. 



