1845.] Thirteenth Memoir on the Lnw of Storms in India. Ill 



tions between these dates for reference, and pass on to Noon of the 

 22d, on which day we have only the Charles Heddle and Appolline on the 

 southern side of their storm, for they were clearly in the same hurricane. 

 The John Adam and Sophia were now of course far out of the influence 

 of the threatening weather which they had experienced. 



Centre of 22nd February. — As the Charles Heddle, at noon 22nd, had 

 a hurricane at about ESE., and as we shall subsequently shew, was 

 scudding in a circle of but little more than 60 miles radius, it follows 

 that the centre bore about NNE. 60 or 70 miles, from her position.* 

 We have not that of the Appolline to compare, but we find that she had 

 the wind at E. by S. also blowing a hurricane, and was lying to, and 

 as she could not be far from the Charles Heddle, I have placed the 

 centre as it relates to the latter vessel only, which will also give the 

 Appolline the wind as she had it, and on about that part of her drift, 

 which is all we can mark for her, at which she was at this time. 



Centre of the 2'drd February. — We have at noon the Charles Heddle's 

 position, as near as her corrected run will give it, and find that she 

 was then on the Eastern range of her first circle, having the wind at 

 North, and that this circle (see post) was of about 122 miles in 

 diameter, or 6 1 miles radius ; which distance to the West gives the ap- 

 proximate position of the centre of the storm for this day. A circle on 

 the general chart cuts the Appolline' 's drift line to the West, as she was 

 drifting that way, so as to give her a wind at about ESE. between which 

 and SEbE. she had it by log. Her drift for want of data, is marked merely 

 as a straight line, but she might have made more southing, and thus 

 have been further from the centre, though on the same bearing from 

 it, and with the same wind. We find on this day also that the Commerce 

 de Bordeaux, first appears to have felt the hurricane, and this agrees 

 well enough as to distance with our centre, which is at 140 miles from 



Engineer, I had a curious account of the dust-whirlwinds, several of which in Upper 

 India he had run after and penetrated. He describes them as forming a thick broad 

 wall of dust, through which it was half suffocation to penetrate, but when in the 

 centre it was nearly calm, with nothing but the wall of dust visible. He farther told 

 me, that he had seen large ones commence, and that they did so in segments, which 

 afterwards united. This is exactly our supposed "streams of wind," but then we 

 know not if the causes on shore are the same ; there may be two or more causes pro- 

 ducing circular atmospheric motion. 



* See however what is subsequently said as to the incurving winds. 



