AN ESSAY ON SOUTHERLY BURSTERS. 147 



"tains, though west of the range it has been known to reach to the 

 Victorian border. This peculiar type of disturbance is accom- 

 panied by an overcast tropical sky, which almost invariably is 

 found preceding the southerly current. 



BURSTERS WITH HIGH TEMPERATURE. 



The temperature is very high ; thunderstorms are prevalent ; 

 and the southerly itself is not, generally speaking, very strong. 

 Still it is, perhaps, more beneficial than the first description of 

 southerly, as it is attended by rain in the northern parts of 

 Australia, and west of the highlands in the northern parts of New 

 South Wales. 



TROPICAL DEPRESSIONS. 



Should the tropical tongue, when it retreats towards the equator 

 travel east, as occasionally happens, the lower part seems to become 

 detached and forms an active rain cyclone on the south-east coast 

 of Queensland. The floods which took place in that locality early 

 in 1892, as well as those on the northern coast of New South 

 Wales, may be ascribed in part to this cause. This opinion, 

 however, it is necessary to mention, rests upon few data and must 

 be taken subject to correction. 



The apparent parting of the tropical tongue to which I have 

 alluded is by no means the invariable, or even the most common 

 form of development. The low pressure always exists in a fluctu- 

 ating state, north of this continent, the isobars sagging down 

 between the high pressures as they pass along, and drawing up 

 again as the high pressures pass under them. In this way they 

 •act upon the low pressure to much the same effect as a succession 

 of ocean waves might do, while passing under a long, pliable, 

 floating body set at right angles to them. 



BURSTERS FROM SECONDARIES. 



The third and last modification results from a secondary. 

 Of this particular variety very few have been recorded on the 

 weather charts. They develop so suddenly that unless they are 

 actually in a state of evolution at the hour when observations are 



