726 Thirteenth Memoir on the Law of Storms in India. [No. 166. 



and West axes of the spirals, or those bounded by the nearest courses 

 to the meridians appear at first sight to be reduced by the effect of the 

 current, and the longer (major) axes also appear reduced by the cross- 

 ings of the old track from the same cause, but the letters A to B, B to 

 C, &c. and a to b, b to c, &c. will show the measurements taken, the first 

 being near the meridional, the last near the horizontal distances. Mea- 

 surements of these parallels are also taken, as in the former case, twice 

 for each circle to obtain a fair average, and are for the vertical axes. 



Mean Diameter. Mean distance 

 from centre. 



1st. 



2nd 

 3rd 

 4th 

 5th 



{ 



1st 



A 



to 



B 



2nd 



B 



to 



C 



1st 



C 



to 



D 



2nd 



D 



to 



E 



1st 



E 



to 



F 



2nd 



F 



to 



G 



1st 



G 



to 



H 



2nd 



H 



to 



I 



1st 



I 



to 



J 



2nd 



J 



to 



K 



112) 



107 f 



85 1 



162 f 



77 I 

 73 i 

 45\ 

 64 (" 

 47 

 6 



w 



110 



55 



" 123.5 



61.7 



75 



37.5 



54.5 



27.2 



54. 



27 



Mean. 41.7 

 When the same kind of measurement is taken between the extreme 

 meridians of the spirals, or from east to west, the results are as 

 follows : — 



st Turn, 



2nd Turn, <[ 



3rd Turn, <{ 



4th Puni, (? J 



' \h to i 



5th Turn, ( * *° { 

 \j to A 



a to b 92 

 b to c 182 

 c to d 89 

 d to e 146 

 e to / 

 /to g 



33 1 

 77/ 



35 

 72 



28 



:an Diam. 



Mean distance from 

 the centre. 



137 



68.5 



117.5 



58.7 



55 



25.0 



53.5 



26.7 





178.9 



44.7 



It is evident here that the second half circle is affected by the current 



which in the run during the first half is against the vessel, diminishing 



the breadth of the circle, and in the second half is in favor of, and 



increases it ; making thus double the difference. The average however 



singularly agrees with the others, as will appear in the following general 



table. 



* Incomplete as in page 725, and the blank cannot be supplied here. 



