ANALOGY BETWEEN LAND VALLEYS 'AND FJORDS. 119 



From all of these considerations tlie writer has heen led to conclude 

 tliat tlie fjords are land valleys greatly depressed. Once in the progress 

 of our science it was supposed that fissures were formed by plutonic 

 forces and left o]kmi. This vision of great open fissures belongs to the 

 past. The drowned valleys diverge in all directions, and the valleys 

 generally are not from orographic folds, except })erhaps two or three in 

 part; nor have the epeirogenic movements detaced their character so as 

 to obscure their resemblance to land forms. What inductions are we to 

 make? Can we deny that these systems are old rivers because they are 

 depressed two miles or more? Must we not accept the physical evidence 

 of the great submergence of the land as here recorded, just as we accept 

 the evidence of the great changes of level registered in the older geologic 

 formations ? 



The gulf of Mexico api)ears to liave been a plain, with the fjords and 

 eml)ayments reaching nearly to its greatest depths. On a smaller scale, it 

 resembles the Mississi])pi valley, or the country between the Appalach- 

 ians and the Rocky mountains. Such being the case, its floor was ele- 

 vated somewhat more than 12,000 feet, and over it drained the Antillean 

 rivers, except the short streams entering the Atlantic basin. It was this 

 precipitous drainage that has removed most of the coastal plains in front 

 of the Windward islands. 



Caril)ljean sea was also another basin which apparently was once a 

 plain, as indicated ])y the deep fjords, altliough the explorations are less 

 complete than those of the Mexican gulf The Windward ridge has been 

 sufficiently investigated to show that the drainage was mostly to the west ; 

 \mt l)etween the Virgin islands and Santa Cruz the natural land valleys 

 appear to have been partially deformed by orogenic movements. 



The sea of Honduras is unlike the other two Antillean depressions, as 

 it is not basin-like, but composed of two valleys, now of great depth. 

 These are parallel to the mountain folds. While the land valleys run 

 into these channels, as in the other cases, yet their greater depth, reach- 

 ing to 20,000 feet, impresses one as being so excessive, and their occurrence 

 between the mountain ranges of from 7,000 to 9,000 feet, elevated in re- 

 cent times, is so suggestive of orogenic action that I am inclined to attrib- 

 ute part of the suljsidence to an abnormal depression of an orogenic fold, 

 though of such a character as not to obliterate the form of the valley. 

 This h3q)othesis would remove the necessity of supposing that the Great 

 Antilles stood 20,000 feet higher than at present. Such unequal depres- 

 sion is in accord with continental movements already descri])ed, l)ut 

 only part of the enormous sinking of the floor of the sea of Honduras 

 could be assigned to orogenic movement, as is sho\Vn by the deep lateral 

 fjords. 



XVII-BuM.. fiKoi.. Soc. Am., Vol. f>, 1894. 



