20 Fifth Memoir on the Law of Storms. [No. 121. 



at Royacottah, and from the Rev. Mr. Garrett at Bangalore, included in 

 his letter. The distance from Madras to Royacottah is about 160 miles 

 W. by S. | S. and from Madras to Bangalore about 215 miles W. f S. 



We see that the centre passed Madras about 8 p.m. on the 16th, and 

 taking it then to have a semi-diameter of about 150 miles, and to have 

 travelled in the same direction as before, it would have passed very con- 

 siderably to the Northward of these two stations, and should have begun 

 to be felt at Royacottah at 8 p. m. on the 16th ; where, as we indeed see, 

 the appearances and wind were suspicious, though unfortunately we have 

 no direction of it marked between 4 p. m. and 2 a. m. where it is only 

 " believed" SE. ; which would make the centre pass to the Northward. 

 At Bangalore we have unfortunately no direction of the wind at all ! 



The Barometrical table however, as compared with that of Madras, is 

 of value, though it would have been far more so had any intermediate 

 heights been observed from between 10 and 4, while the weather was 

 so threatening. Taking the extreme Madras depression to have been at 

 7. p.m. of the 16th 29*0690, and that of Royacottah and Bangalore 

 at 4 p.m. on the 17th, and that those epochs indicate the passage of 

 the centre, we have then 21 hours for the time it took to travel from 

 Madras to Royacottah, or 1 60 miles, which gives about 8 miles per hour 

 as its rate of travelling when it reached the land, and had to force its 

 way over ridges of hills ; while at sea it was, as we have seen, travelling at 

 the rate of 14~ miles per hour, a very remarkable instance of the effects 

 which ridges of mountains (for Bangalore is at least 3000 feet above the 

 sea, and the crests of some of the Eastern Ghauts thereabout cannot 

 be much less than 5000 feet) produce on the rate of motion of storms 

 from seaward. 



It is worth while to compare this retardation from 14 miles to 8 miles 

 per hour, or say one half, with what the Cuttack storm of 1840 (Third 

 Memoir*) appears to have also experienced from the same cause, but where 

 the ranges of hills were perhaps not so high. This storm seems to have 

 been checked from about 350 miles per day, its greatest rapidity, to 113 

 and 175 miles, or about one half its velocity on its approach to the land. 



We do not know any thing of the Cuttack storm inland. The 

 Madras storm, which we are now considering, seems to have been nearly 



* Journal Asiatic Society, vol. ix. p. 1009. 



