24 Ml' Retliield uv. tlie Hurrhune.'i and 



The great value of the barometer to navigators is becoming 

 well understood, and its practical utility might be greatly in- 

 crcasotl by hourly entries of the precise height of the mercurial 

 column, in a table prepared for the purpose. Its movements, 

 unless carefully recorded, often escape notice or recollection, 

 which may easily happen at those times when a distinct know- 

 ledge of its latest variations might prove to be of the greatest 

 importance. 



In the foregoing statements, om* design has been to designate, 

 in a summary manner, the principal movements which, in these 

 regions at least, constitute a storm ; and we do not attempt to no- 

 tice the various irregularities and subordinate or incidental move- 

 ments and phenomena of the atmosphere, with which a storm 

 may chance to be connected, or which may necessaiily result 

 from such violent movements in a fluid which is so tenuous and 

 elastic in its character. It may be remarked, in general, that 

 the most active or violent storms are usually the most regular 

 and uniform in the development of those characteristic movements 

 which we have already described. It is also probable, that the 

 vortex or rotative axis of a violent gale or hurricane, oscillates 

 in its course with considerable rapidity, in a moving circuit of 

 moderate extent, near the centre of the hurricane ; and, such an 

 eccentric movement of the vortex may, for aught we know, be 

 essential to the continued activity or force of the hurricane. 

 Such a movement will fully account for the violent floxvs or 

 gusts of wind, and the intervening hills or remissions which are 

 so often experienced towards the heart of a storm or hurricane, 

 when in open sea ; but of its existence we have no positive evi- 

 dence. 



It frequently happens that a storm, during the first part of 

 its progress over a given point, fails to take effect upon the sur- 

 face, while it exhibits its full activity at a greater altitude. This 

 commonly happens, when this portion of the storm arrives from, 

 or has recently blown over, a more elevated country, or is pass- 

 ing or blowing from the land to the sea. On land, the most 

 violent effects are usually felt from those storms which enter and 

 blow directly from the open ocean upon the shores of an island 

 or continent. Upon the latter, under such circumstances, the 

 first part of the gale is usually the most severe, and that coast 



