254 



Astrseans. By the powerful action of the waves on the shallow 

 bottom, these remains are broken and ground upon each other, 

 and their form is lost. 



The lime powder which results from this pulverizing action 

 furnishes the cement which fills the shells and unites the pieces 

 into one solid mass, Magonnerie hon Dieu (God's Masonry) as the 

 negroes of the French colonies call it. In consideration of these 

 facts the first part of our question may be answered in the affii'm- 

 ative. 



But whether the whole coast is constantly and gradually rising, 

 (as we know is the case with the coast of Sweden,^) or whether 

 those different layers of that submarine pavement have been 

 thrown up at various periods, by sudden volcanic agencies, I am 

 at a loss to decide from my own observations. I will only state 

 that the layers which lie now just above low-water mark, are (for 

 instance, in some places in the neighborhood of Jeremie) quite 

 undisturbed banks, running in a plain parallel to the level of the 

 sea. This seems rather to favor the idea of a gradual rising 

 than of a sudden upheaving, and the latter would be more likely 

 to fracture the layers and to change their original horizontal 

 position into an angle towards the horizon. 



I conclude, from the information afforded me, that this lime- 

 stone formation must extend over the whole northern part of 

 Hayti, from its western cape (Tibouron) to the neighborhood of 

 Port-au-Prince. Further, the rocky part of the sea-shore of Bar- 

 badoes, Maria Galante, of Grand-terre in Guadaloupe, of An- 

 tigua, St. Bartholome, St. Martin, Arguilla, and Santa Cruz, seems 

 to be of the same composition and age. I should judge so, also, 

 from an account of William Maclure, published just forty years 

 ago in the Journal of the Academy of Natural Sciences of Pliila- 

 delphia, vol. i. p. 134, et seq. Further also, the honeycomb 

 limestone of Jamaica is the same rock, according to a communi- 

 cation of my friend Dr. Hyde,^ who lived in that island for many 

 years. 



1 According to the observations of Leopold von Buch, Hallstroem, and Lyell, the 

 whole northern coast of Sweden and that of Finland is continually rising at the 

 rate of four feet in a century. See also Humboldt's Kosmos, I. p. 315 and p. 472, 

 et seq. 



2 Dr. J. S. Hyde, of New England, a zealous and experienced conchologist, by 

 whom were collected many of the Jamaica land-shells, which were described by 



