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Y erde Islands, and had the north-east trade almost the whole 
Avay 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 SYV. 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 
Aveek evident indications from the set of a heavy SAvell that 
another cyclone is hoav running down to the Mauritius. 
The result is, that although we have had trade Avind clouds, 
Ave have had no S.E. trades in the Indian Ocean, and Ave are 
hoav, and have for some days been in the N.W. monsoon, and 
have been nearly boiled by its Avarm 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 hears 
strongly upon the theory of hurricanes, and which I want 
you to put in train. All old seamen agree that the trade 
Avinds are variable in force and direction. 1 should be glad 
if Mr. Mosley, or some one Avho is from time to time in 
communication with Capt. Maury, would try to get him to 
discuss his collection of above 500,000 trade Avind observations 
in order of time, as this question hears 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 bctAvccn the theoretical rate 
of cooling in ascending, and the actual, indicates a rapid 
transmission of the atmosphere from above to beloAV, and 
vice versa, continually going on. We may believe that 
during thunderstorms this interchange goes on with much 
