Strictures on Dove's Essay " On the Law of Storms." 137 



Art. XIV. — Strictures on Prof. Dove's Essay " On the Law of 

 Storms ;" by Robert Hare, M. D., Professor of Chemistry in 

 the University of Pennsylvania.* 



TO THE EDITORS OF THE AMERICAN JOURNAL OF SCIENCE. 



Dear Sirs — Since forwarding my communication containing 

 additional objections to Mr. Redfield's theory, I have perused Prof. 

 Dove's Essay on the Law of Storms. I now send to you for the 

 Journal, some strictures to which I conceive that essay liable. 



But first allow me to take due notice of the note subjoined by 

 you to the first page of my last communication, in which you 

 allege your understanding of Mr. Redfield to be, that he repre- 

 sents " the whirlwind as the cause of the violence, not the cause 

 of the whirlwind." The language on which my understanding 

 was founded, represents "a rotative movement of unmeasured 

 violence" as "the only cause of violent and destructive winds or 

 tempests." But admitting your impression to be correct, does it 

 make the error less to say that a whirlwind is the only cause of 

 its own violence ? Besides, where is the difference between 

 producing a whirlwind and producing the violence of a whirl- 

 wind ? Is it contended by Mr. Redfield that there are two causes, 

 one producing wind, the other the force or violence of wind? 

 But is there not a great mistake made by Mr. Redfield and other 

 advocates of the whirlwind theory, in treating gyratory motion 

 as a cause of violence ? Is it not evident, that whatever may be 

 the cause or causes of aerial currents, gyration, instead of accel- 

 erating that velocity on which violence is dependent, must, by 

 the expenditure of momentum resulting from collision with inert 

 portions of the atmosphere consequent to centrifugal force, cause 

 a great loss of velocity. (See my objections, par. 65.) 



100. I have not been enabled to discover that Prof. Dove at- 

 tempts to assign any cause for violent winds. Assuming that a 

 wind, sufficiently violent, is blowing from south to north, he in- 

 geniously makes a new application of the old doctrine of Halley, 

 by which the westerly motion of the trade winds is ascribed to 



* We had hoped to have published Prof. Dove's Essay, on which Dr. Hare com- 

 ments, in connection with these ' strictures,' but are obliged from the crowded state 

 of the present number to postpone it to our next. — Eds. 



Vol. xliv, No. 1.— Oct.-Dec. 1842. 18 



