141 



FOR THE CABINET, 



Two specimens of preserved butterflies, from Malta. Accompanied 

 by explanatory letters from the donor, and the Rev. Dr. Bc- 

 thune. — From Mr. William Winthrop Andrews, U. S. Consul, 

 Malta. 



Dr. Hare made an oral communication, in which he pointed 

 out what he conceived to be very glaring errors in Mr. Red- 

 field's opinions, which may be briefly stated as follows: — 



1st. That all atmospheric currents, whether designated as trade 

 winds, gales, storms, tempests, tornadoes, thunder gusts or hurri- 

 canes, are to be explained by a reference to the " simple conditions of 

 the great laws of gravitation ;" the agency of electricity being neglect- 

 ed, and " the theory of calorific rarefaction''' renounced. 



2d. In alleging the existence of " opposing and unequal forces" 

 without specifying their nature, or accounting for their existence; 

 although implying that they are the effects of '■'■the simple conditions 

 of the great laivs of gravitation.'''' 



3d. In assigning to "all fluid matter a tendency to run into whirls 

 or circuits, when subjected to opposing and unequal forces ;" which 

 can be true only in some peculiar cases of the influence of such 

 forces. 



4th. In treating of all storms as whirlwinds ; or in other words in 

 making the words storm and whirlwind synonymous, and yet repre- 

 senting a rotative movement in the air, or in other words a whirl- 

 wind, " as the only known cause of violent and destructive toinds 

 or tempests;" so that a whirlwind is the only cause of its own 

 force ! 



5th. In averring that " all narrow and violent vortices have a 

 spiral involute motion, quickening in its gyrations as it approaches 

 the centre or the axis of the whirl;" whereas, it must be evident that, 

 when a whirl is the consequence of forces applied at the periphery of 

 any mass, the consequent velocity in any part of the mass will be 

 less in proportion to its proximity to the axis ; and that the only case 

 in which it will be greater in proportion to the nearness of the axis, is 

 where the motion proceeds from some competent cause acting at the 

 centre. 



6th. In admitting the gyration which he considers as the cause of 

 storms, to quicken as it approaches the axis of motion, without per- 

 ceiving that this characteristic is, as above stated, irreconcilable with 



