prevalent Disorders, Sj-c, "with Volcanic Emanations. 629 



than ever known, and *was attended by frosts. The sky was 

 always hazy, calm, and dry ; the wind always from the south. 

 This extended over the first twelve degrees of south latitude. 

 But the climate of New Grenada is subject to severe frosts at 

 night, even during the season of most scorching heat. The 

 inhabitants of the country desolated by the earthquakes at 

 Pasto, &c., in January, 1834, suffered from this most dread- 

 fully. 



Towards the end of August, 1804-, the maize in New Mexico 

 was so completely destroyed by intense frosts, that famine, 

 and its attendant pestilence, carried off no less than 300,000 

 persons. Now, 1804 was a close season, when little ice was 

 melted in the Atlantic; and the same may be said of 1809. 



Were these frosts caused by ice in the Atlantic ? Yet, why 

 not ? Again, are the horrid frosts in Persia and China, and 

 in Africa (12° n.), caused by this melted polar ice? As has 

 been well observed by M. Parrot, the cooling of the sea, by 

 the melting of the ice, would be like cooling Geneva Lake 

 with a cubic fathom of water of the temperature of melting 

 ice : and to cool Europe this way would be still more pre- 

 posterous.* M. Parrot is contending against Fourrier's theory 

 of a central fire ; and says, in continuation, that, if such a 

 fire exists, it would be proved by the increased temperature 

 of the sea at great depths. He proves that the temperature 

 at sea decreases with the depth ; and alludes to Mr. Scoresby's 

 experiments in the deep sea between Greenland and Spitz- 

 bergen, where the heat increased even amidst ice ; and justly 

 observes, that this heat was owing to the volcanic mass below.f 



M. Parrot rejects in toto the idea of a central heat ; and 

 considers that all the phenomena connected with terrestrial 

 heat arise from volcanic actioyi, which has existed from the 

 earliest times ; and still operates, though with much less 

 intensity than at ancient eras. In this case I am completely 

 borne out in my speculations by M, Parrot. 



Notwithstanding, in the above remarks, 1 am far from 

 wishing to deny any indubitable influence that the ice may 

 have in producing sudden paroxysms of cold in the direction 

 of the wind blowing across it. The chill, in the spring of 

 1833 and 1834, and, perhaps, an occasional coldness since, 

 were, as I believe, occasioned by the wind bringing to our 

 shores a stratum of " ra'ixi moist air :" but I dispute that the 



* Considerations sur la Temperature du Globe, &c. {Memoires de 

 VAcademie de St. Petersbourg.) There is a paper on the same subject, by 

 the same author, in the Bulletin de Feritssac. 



f Vide Quarterly Revieiv, xviii. 452-8, where are some sensible remarks 

 on this subject. 8ee, also, De la Beche, Manual of Geology y p. 22. 



s s 3 



