582 



Scitntifit Intelligen$e. [No. 10, new series. 



" grande secheresse qui ait ete observe edans les basses regions de 

 " la terre." I did not record my Saussure* at Oyacaud, but 6 

 days previous, on the 25th February, and in the same vicinity, I 

 observed that it stood at 5 p. m. at 48°, the Dry and Wet bulbs 

 standing on the same day at 97° and 67° a difference of 30* = to 

 a Dew Point of 47°. 



16. In fact the heat and dryness of the Easterly winds in the 

 Palghat opening, in the months of February, March, April, are 

 fully equal if they do not exceed that of the land winds at Madras 

 in the months of May and June ; and they are succeeded here, as 

 there, sometimes as early as 10 or 11 a. m. by exceedingly strong 

 sea breezes from the W. varying as regards the hour of arrival, in- 

 land, according to the distance from the sea, and to the collision 

 of these two winds so differently constituted in regard to tempe- 

 rature, vapour, and electricity may perhaps in part be ascribed the 

 thunder storms that so often occur. The natives of those districts 

 have a belief of the kind and attribute the thunder storms and 

 sudden falls of rain to the meeting of the dry winds of the Eastern 

 and moist winds of the Western countries. 



17. Whilst the Dry and Wet bulbs at Oyacaud, 35 miles from 

 the sea, were on the 2nd March 96° and 62° they stood on the 

 same day at Cochin on the sea shore at 80° and 76°. The land 

 or Easterly wind continued on that day, to blow at Oyacaud till 

 past 4 o'clock; a light sea breeze setting in only at 6J p. m., but 

 it had reached Tritchoor 20 miles nearer the' sea by nine a. m., 

 thus taking 9 hours to pass over an interval of 20 miles. The vast * 

 mass of vapour almost in a state of saturation which in this season 

 rolls in from the Western Coast with a velocity in general of from 

 10 to 15 miles per hour, on meeting with the intensely dry air in 

 the centre of the Palghat opening which has an equal velocity to 

 the Westward, may well be supposed to give rise to those changes 

 in the normal conditions of the atmosphere which are followed by 

 thunder storms and falls of Hail. 



18. I have a large collection of observations of the fall of 

 rain, and of the state of the Hygrometer, in the Palghat opening, 

 as well as in many other localities in Travancore and Cochin, 



* An instrument received from Paris. 



