SECOND ANNUAL REPORT-STRUCTURE OE FLORIDA. 
47 
ridge, which has grown up from the sea-floor, to the altitude of about five thou¬ 
sand feet; and a somewhat similar elevation in the archipelago of the Bahama 
Islands. Neither of these ridges has a mountainous character. Indeed, it is at 
first sight difficult to find the analogues of these great anticlinal-like folds in 
the existing structures of the land. They can hardly be classed with any of our 
known table-lands, for the reason that such elevations are in all cases more or 
less associated with definite mountain folding. The only similar structure which 
is known to me is that exhibited in the “Cincinnati anticlinal,” that well-known 
ridge extending from near Columbus, Ohio, to Northern Alabama. This eleva¬ 
tion in length and breadth may be compared to that of Florida, though it never 
had more than one-half the height of the Floridian peninsula. 
It should be remembered that there is to be included with the 
peninsula the submerged plateau which borders it on either side and 
extends out to the abysmal depths of the ocean, and when Prof. 
Shaler speaks of a broad earth arch he includes in it not only the 
land but this submarine plateau which in places extends over 150 
miles beyond the coast and which descends steeply to profound depths. 
In a later paper, Prof. Shaler 1 reiterates the same view and states that 
he regards Florida as a broad submarine fold, approximately 600 
miles in length which has risen from a depth of about 5,000 feet. 
In commenting on the hypothesis advanced by Prof. Shaler, Dr. 
Dali 2 says: 
In considering the topography of Florida, it has been customary among 
geologists and others to speak of the “central ridge,” “elevated axis,” and in 
the latest contribution to the subject Prof. Shaler regards Florida as “formed 
of lowlands rising as a broad fold from the deep water on either side to a vast 
ridge, the top of which is relatively very flat, there being no indication of true 
mountain folding in any part of the area.” In an extremely wide and general 
sense, it is, of course, true that the peninsula forms a great fold, but in the 
ordinary and literal meaning of the words this description conveys an inaccurate 
idea of the structure of the region. 
Dr. Dali regards the structure of Florida as characterized by low 
folds approximately parallel to the general trend of the peninsula. 
By means of railroad profiles he finds indications of two well defined 
ridges, one near the Atlantic coast and another near the Gulf coast. 
A third ridge is noted in the vicinity of Brooksville and Plant City. 
The eastern ridge which forms the eastern boundary of the central 
“lake basin” includes the well known Trail Ridge and was thought to 
be composed of “Miocene” rocks. In this connection “Miocene” is 
probably intended to include the Oligocene rocks belonging to the Apa¬ 
lachicola group which were then known as Miocene. The western 
ridge forms the western boundary of the central “lake basin” and 
1 Shaler, N. S., Relation of Mountain Growth to Formation of Continents. 
Bull. Geol. Soc. Amer., Vol. 5, 1894, pp. 206. 
2 Dali, Wm. H., Neocene of North America, Bull. U. S. Geol. Survey NA 
84, 1892, pp. 87. 
