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LAW OF STOEMS. 

 By the Right Revd. Bishop Bromby, D.D. 



[Bead Uth October, 1879.] 



Ill 1874 Iliad the lionour of reading a paj^er to this Society 

 upon the Law of Weather and Storms. I then stated that 

 my principal object, in the interests of our merchants and 

 sailors, was to induce others on land, or on ship-board, to 

 register observations, which, when collated with those 

 reported in other countries in the Southern Hemisphere, 

 might lead to some general and useful results. It is now 

 assumed that a circular storm, to use the definition of 

 Buchan, is simply the variation of the atmosphere attempting 

 " to flow in upon a central area of low pressure in an in- 

 moving spiral course." I stated that the rule for determining 

 the ajpproach as well as direction of the storm had been in 

 somewhat rough and familiar language laid down by Ballot, 

 '* If you stand with your back to the wind, the barometer 

 will be lower on your left hand than on your right." This, 

 however, only describes storms in the other hemisphere — the 

 W. India hurricanes, and the typhoons of China, which move 

 from right to left, i.e., in a direction contrary to the move- 

 ments of the hands of a watch. A man looking eastward in 

 the British Isles, and finding that the barometric pressure at 

 the north of Scotland is, say, i inch less than on the south 

 of England, may look out for a westerly gale. In our Tas- 

 manian waters I believe it will generally be found that a 

 storm arises from a conflict between an easterly and westerly 

 wind, the easterly being always found to flow on the polar 

 side of the westerly. It should be borne in mind also that 

 the direction of the force of the wind does not depend upon 

 the height of the barometer, i.e., upon the barometric pres- 

 sure at the station where the storm occurs, but upon the 

 difference of barometric pressure over a given distance. 

 I stated in my last paper that the force of a wind was 

 regulated by the distance between the station where the 

 storm is felt from the point where at that moment the 

 barometric reading was the lowest, so that if that distance 

 was small the force of the storm would be in the same pro- 

 portion more violent. This opinion has been questioned 

 among American authorities. 



The atmosphere, like the ocean, is one great fluid, and 

 phenomena need to be noted in order to connect effects in 



