924 Mr Redfield's Observations on the 



an hour. The foregoing remarks are by no means hypotheti- 

 caljbut are the result of long continued observation and inquiry. 



It will hardly escape notice that the track of most of the 

 hurricanes, as presented on the chart, appears to form part of 

 an elliptical or parabolic circuit, and this will be more obvious 

 if we make correction, in each case, for the slight distortion of 

 the apparent course in the higher latitudes, which is produced 

 by the plane projection. We are also struck with the fact 

 that the vertex of the curve is uniformly found on or near the 

 80th degree of latitude. In connection with this fact it may 

 also be noted, that the latitude of 30° marks the external li- 

 mit of the trade winds, on both sides of the equator ; and, per- 

 haps, it may not prove irrelevant to notice, even further, that 

 by the pai'allel of 30°, the surface area, as well as the atmo- 

 sphere of each hemisphere, is equally divided ; the area between 

 this latitude and the equator being about equal to that of the 

 entire surface between the same latitude and the pole. It is 

 not intended, however, to make these facts the basis of any 

 theoretical inductions on the present occasion. 



A variety of deductions may be drawn from the general facts 

 which we have stated, some of which, though deeply interest- 

 ing to the philosopher and votary of science, might be out of 

 place in this short memoir. For ourselves, we disclaim any 

 bondage to existing theories in meteorology ; and shall, on the 

 present occasion, only proceed to notice a few of the more prac- 

 tical inferences which, to navigators and others, may, perhaps, 

 be of no doubtful utihty. 



1. A vessel bound to the eastward between the latitudes of 

 32° and 45° in the western part of the Atlantic, on being 

 overtaken by a gale which commences blowing from any point 

 to the eastward of S.E. or E.S.E., may avoid some portion of 

 its violence, by putting her head to the northward, and when 

 the gale has veered sufficiently in the same direction, may safely 

 resume her cour?e. But by standing to the southward under 

 like circumstances, she will probably fall into the heart of the 

 storm. 



2. In the same region, vessels, on taking a gale from S.E, 

 or points near thereto, will probably soon find themselves in 

 the heart of the storm, and after its first fury is spent, may ex- 



* 



