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Verde Islands, and had the north-east trade almost the whole 

 way down at E.S.E. Our south-east trade, which we picked 

 up in the Bight of Benin, came out at S.S.W., hut we 

 afterwards on going to the S.W. got it in its proper direction. 

 We were on the skirts of three cyclones between the Cape 

 and Amsterdam Island ; and there have been within the last 

 week evident indications from the set of a heavy swell that 

 another cyclone is now running down to the Mauritius. 

 The result is, that although we have had trade wind clouds, 

 we have had no S.E. trades in the Indian Ocean, and we are 

 now, and have for some days been in the N.W. monsoon, and 

 have been nearly boiled by its warm damp atmosphere. The 

 Captain has told me that for days since leaving the Cape he 

 has not known what to make of the weather, and his 

 experience of these seas (which is great) has only served to 

 puzzle him. This leads me directly to a point which bears 

 strongly upon the theory of hurricanes, and which I want 

 you to put in train. All old seamen agree that the trade 

 winds are variable in force and direction. I should be glad 

 if Mr. Mosley, or some one who is from time to time in 

 communication with Capt. Maury, would try to get him to 

 discuss his collection of above 500,000 trade wind observations 

 in order of time, as this question bears directly upon that of 

 which I have spoken to you, viz., the perturbations, so to 

 speak, of the hurricane orbits of the West Indies, by which 

 their tracks sometimes pass over St. Domingo and sometimes 

 do not." 



Dr. Joule made a communication " On the Probable 

 Cause of Electrical Storms." 



The very close correspondence between the theoretical rate 

 of cooling in ascending, and the actual, indicates a rapid 

 transmission of the atmosphere from above to below, and 

 vice versa, continually going on. We may believe that 

 during thunderstorms this interchange goes on with much 



