174 HENRY A. HUNT. 



be fully eight hundred miles. About the \ there was a well 

 •defined circulation of fresh winds, north-west and south-west, 

 rain had fallen in the northern districts of South Australia and 

 Queensland, and during the forenoon of 13th there were passing 

 thunder squalls and half formed festoon clouds, which were in 

 rapid motion and had a mild disturbed appearance. All day the 

 upper strata of cloud was coming from north-west to west, during 

 the forenoon temperature in the shade rose to 81*8°. At 3 p.m. 

 seven-tenths of the sky was obscured by cumulus, cirro-cumulus, 

 cirrus, and stratus. At 4 p.m. they were much the same, except 

 that in the north the cumulus clouds were bolder and looked like 

 a wall of rocks, snow-white in colour, with horizontal seams or 

 joints. At 5 p.m. thunder clouds seemed to be in all directions. 

 At 6 p.m. a southerly roll could be seen low down in south-west, 

 with much lightning playing about over it in the cumulo-stratus 

 and cumulus. 



As the burster came on, the stratus on the horizon rose 

 .gradually up and revealed its true character, at 6*25 p.m. the 

 roll was about 4° in diameter, and had a lower fringe like a very 

 narrow roll of cumulus, above this a dark black roll of stratus 

 surmounted by a feathery fringe, turning up and trending to 

 south, while under the great roll at its northern end, could be 

 seen a well defined shower with rain drifting to north at an angle 

 of 45°. (See Plate 8 taken at 7 p.m.) Above this well defined roll 

 cloud another fainter and less defined one is clearly but faintly 

 -shown in the negative. The whole storm could be seen to great 

 advantage from the Observatory, and the roll came along getting 

 more and more defined, showing all the features just described 

 irom 6*25 to 7 p.m., including the shower and the duplicate roll 

 above. At 7 p.m. it looked very close to us, and could nob have 

 been more than three or four miles away, for five minutes later 

 the squall with a velocity of forty-two miles per hour and the rain 

 were upon us. On the photograph taken at 7 p.m., (reproduced 

 as Plate 8) the altitude of the lower edge measures 5°, and taking 

 the distance to be four miles, the actual height above the ground 



