REVOLVING STORMS. 117 



being about 12 hours, but its entire duration was in many 

 places more than twice that period." * 



The literature bearing upon storms and hurricanes 

 is most voluminous, and a catalogue of upwards of a 

 thousand works, reports, and other papers devoted to 

 this subject was published by Mr. A. Poey of Havana 

 in 1865,1 some of them dating back as far as the 

 beginning of the sixteenth century, and many hundreds 

 have since then been added to this long list. 



But though the laws which govern these phenomena 

 have been the subject of debate, in this way, for 

 centuries, there still remain many points upon which 

 the opinion of authorities is undecided. 



It is, however, a well-ascertained fact that hurricanes 

 have two distinct motions the principal of which is 

 of a revolving or gyrating character; and the other 

 an onward and progressive movement; of this rota- 

 tory storm a miniature representation may frequently 

 be seen in gusts or eddies of wind, carrying round 

 with them bits of straw and dust, on any stormy 

 day. 



It is this whirling motion which is so terribly de- 

 structive, and which seems to act with continually 

 increasing violence from its exterior margin inwards 

 towards its centre, or vortex ; at which point the 

 terrible " lull of the storm " occurs, and a complete 

 calm generally exists, with the sun perhaps still 

 shining brightly by day, or the stars by night 

 whilst all around this central calm, is the dark bank 

 of cloud where the hurricane is still raging in its 

 greatest intensity. 



* The Law of Storms Considered Practically, by W. H. Rosser, 1876, 

 p. 10. j Ibid. p. 2. Ibid. p. I, opening paragraph. 



