MULL. METEOROLOGY. 545 



of the gales. On one of the occasions which I have 

 excepted, it was afterwards known that the same gale, 

 which I experienced with great severity in the island of 

 Egg, had been of great extent, since in that storm the 

 loss and dispersion of the Jamaica fleet in 1815 took 

 place. It is equally probable that in the other casea 

 where the barometer was affected, the gale had also 

 occupied a wide range, although not so remarkable as to be 

 recorded, like the former, in the public prints. On that 

 occasion my barometer fell half an inch in the space of 

 .four hours, although the gale in itself was neither more 

 severe nor of longer duration than many which had 

 occurred through that long period of tempestuous 

 weather. That most of these gales w.ere local, or ex- 

 tended through a small space only, was confirmed when 

 I afterwards arrived on the east side of Scotland, where 

 the whole period had been characterized by continued fine 

 weather and an uncommon drought ; whereas on thewes- 

 tern coast scarcely one day in five was free from torrents 

 of rain.* It is perhaps scarcely necessary to say that 

 these observations were confirmed by corresponding re- 

 , marks made on too distant stationary barometers, since 

 it is now well known that a general agreement is found 

 .to exist between these, within certain limits as to distance 

 in position. 



It follows therefore that the barometer is not affected 

 by local atmospheric changes, although these are consi- 

 derable; neither sinking to denote rain or wind, nor 

 rising to indicate fair weather, except in those cases 



* I may add that this observation has been confirmed on innumerable 

 other occasions ; some of the instances having been even much more 

 remarkable. In one storm, which occurred in Sutherland, the barometer 

 gradually rose an inch in twenty-four hours, namely, from 29,2 to 30,2 

 during its continuance, and subsided to the same level after it had 

 ended. Neither did the effect result from change of wind, as the gale 

 was from the west, and the wind, which had previously been from the 

 eastward, returned to that quarter after its termination. This fact pre- 

 sents a remarkable example of a double anomaly. 



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