1839.] on the 3d, \th\ and 5th of June, 1839. 585 



I have next delineated the whole of the tracks with the winds at 

 noon upon the general Chart, and from these are deduced the centres, 

 which last I have marked by a single circle or two for each day, and 

 from the centres I estimate the course of the hurricane. To render the 

 whole more distinct, three diagrams are also given, to half scale, upon 

 which I have a few remarks to make. 



In considering these diagrams and tables, the reader will be struck 

 with some few anomalies ; that is, he will observe that the arrows do 

 not always show the wind as blowing in exact circles, and that in 

 one or two instances, they are altogether different from the others, 

 though not absolutely contradictory. 



I take these few discrepancies mostly to arise from some one of the 

 following causes : — 



I. The carelessness of many in noting the direction of the wind, or 

 the not noting it at the time. 



II. Their erroneous estimation of its direction when looking at a 

 weather-cock or dog- vane, and, if a ship is going fast, the not allowing 

 for the effect of her motion upon it.* 



III. On shore, local circumstances, such as houses, hills, rivers, and 

 the like, which may often produce differences. 



IV. At sea the vicinity of the land, ranges of mountains, &c. which 

 when the gale or hurricane strikes them, occasion a re-action altering 

 the direction of the wind. 



V. As it has been necessary to fix upon one instant of time at 

 which to compare the wind and weather experienced by different ves- 

 sels, noon has of course been chosen ; but when the winds are varying, it 

 may occur that the one marked about noon is a little more unfavour- 

 able to the appearance of the diagram than that which perhaps was the 

 predominant one throughout the day ; as, however, it would have^ 

 appeared like accommodating the facts to the hypothesis, I have pre- 

 ferred allowing them to stand as marked, taking a mean point where 

 the limits of the variation of the wind are expressed, such as SE. 

 when the words " between South and East," are used. 



VI. The positions of the vessels are rarely accurately ascertained in 

 a severe gale. 



Let us consider these causes separately. The careless habits of 

 seamen are well known, and that these should extend to what is 

 apparently the unimportant matter of noting the exact direction of the 

 wind is not surprising, and is well known to every intelligent man, 

 who has commanded a vessel. In severe weather too when a vessel 



* The eddy wind from the mizen staysail will sometimes in a small ship affect the 

 door-vane. 



