Law of storms

In 1874 I had the honour of reading a paper 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 inmoving spiral course." I stated that the rule for determining the approach 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 movements of the hands of a watch.