SOUTHERLY BURSTERS. 47 



On the morning of the 15th February weather chart No. 1 gives 

 the barometic conditions over Australia and New Zealand, con- 

 ditions which had materially hardened since the 14th, winds 

 generally were fresher and conforming to the isobars, and weather 

 fine and warm in the eastern colonies. Up to noon there were 

 light cirro-cumulus clouds in the south-west, at 1 p.m. they had 

 become much more dense and somewhat thundery looking, and 

 seemed to be working round the horizon to the north, with one 

 remarkable mass of cumulus. The following diagram of this date 

 shows the instrumental changes during this southerly. 



At 2 p.m. south-west clouds slightly advanced, at the same time 

 those low down obscured by haze or dust : up to 2 p.m. north-east, 

 east, and south-east horizons beautifully clear. 2 '40 p.m., clouds 

 still working further round to due north, with a few light cirrus 

 forming and evaporating east of this point, and a general drift to 

 the east, then thunder cumulus worked up from south-west very 

 slowly, the advanced cirrus reaching Sydney at 3 '30 p.m. ; no 

 trace of cloud observable with surface wind up to this time ; a 

 roll of cloud appeared at 3' 15 p.m. above south horizon (See 

 Plate i, taken at 3-43 p.m.), which seemed to be made up of 

 a band of stratus surmounted by cumulus 30 in length ; at 4 

 p.m. the roll merged into the general clouds, which were then 

 fringed overhead and stratified on the southern boundary, beyond 

 which the sky was clear for a space of about 10, at the same 

 moment an uneven roll of heavy cumulus began to rise above the 

 horizon ; as it lifted, the sky still further beyond was clear. Up to 

 this hour, 4 p.m., only one strata of cloud visible, and that moving 

 from south-west ; a very dense and extensive cloud of smoke to 

 south-west, which worked backwards and forwards between north- 

 west and south-east on the horizon. At 4-20 p.m. the eastern 

 point of the roll was immediately over Botany Bay, the western 

 limit extending indefinitely to the west. (See the details in Plate 2, 

 taken at this time.) Small shower at 5-15 p.m. The cloud roll 

 then seemed to melt away like the earlier one, and the upper 

 clouds still moving from south-west became very wild looking, 



