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mmiuiuin barometric pressure witliiu tlie next 24^ lioiirs, and 

 Cape jN"ortliumberland some six or twelve hours after. Even 

 in sucli a case as this, it is not always positively certain that a 

 given kind of weather will follow. There are, of course, 

 certain rules as to the kind of w^eather we may expect at 

 different parts of a storm's path. These are purely empirical, 

 and have been collated from observations made on Australian 

 storms since the establishment of the Western Australian 

 telegraph. Any rules that have been previously discovered in 

 the northern hemisphere have been found to be of no practical 

 use for application here. We find that we must carefully 

 investigate as far as possible our own storms, and find out 

 empirical laws therefrom for our practical guidance. As a 

 matter of fact, one rule seems to be pretty firmly established — ■ 

 that with a certain class of depressions, occurring mostly in 

 winter, the weather is fine a long distance ahead of the coming 

 storm ; as the centre approaches the sky becomes: clouded over 

 first wdth cirrus, then cumulus, or rather cumulo- stratus. Light 

 rain sets in some time before the lowest pressure, and while 

 the wind is still light from the north ; but after the lowest 

 pressure has passed the wind veers to the S.W., the clouds 

 change into scattered watery cumulus, nimbus, and scud ; the 

 wind blows strongly, and the rain descends in heavy showers. 

 I think I may say that this is the usual type of winter dej)res- 

 sions ; at all events, most of those during the late winter have 

 been of this sort. But, then, the light rain preceding the centre 

 sometimes starts two days, sometimes only a few hours, prior 

 .to the passage of minimum pressure. Sometimes the light rain 

 is absent, and we experience a strong northerly gale. Some- 

 times the weather clears almost directly after the passage of 

 the centre, and sometimes remains showery for a w^eek. We 

 might think it would be very easy to tell what particular sort 

 of weather was connected with any particular part of the 

 movement by noting the change at the various w^estern stations 

 as the storm centre passed them. But suppose Albany reports 

 fine weather almost up to the time of minimum pressure, fol- 

 lowed by very heavy rain, Esperance Bay heavy rain followed 

 by scattered showers, and Eucla a strong northerlj^ gale with 

 no rain and a veer to west or south-west with fine weather 

 after the passage, while Streaky Bay and Port Lincoln report 

 threatening weather, it is rather difficult to say with any 

 degree of certainty which of these different phases will be pre- 

 sented as the disturbance passes Adelaide. AVe are never at 

 all sure of a depression until Eucla shows indubitable signs of 

 its presence ; but w^hen once it has passed Eucla it is almost 

 certain to travel eastward or south-eastward, and thus for a 

 large number of storms we have warning at least twelve hours 

 in advance. 



