MINERAL INDUSTRIES LIiME AND LIMESTONE. 45 



Analysis of limestone from 25 miles south of Lake Okeechobee. 



Per cent. 



Calcium oxide, 44.68%, equivalent to calcium carbonate 79.8o 



Magnesium oxide, 0.38%, equivalent to magnesium carbonate 0.76 



Phosphoric acid trace 



Insoluble, silica, etc ; 1 7.90 



Another limestone, seen on the North New River canal, is 

 cut into by the dredge at a distance of about 42 to 52 miles from 

 Lake Okeechobee. This limestone is granular and more or less 

 distinctly oolitic in structure and is not so hard as that seen nearer 

 the Lake. The surface of this rock becomes very rough on ex- 

 posure, presenting a characteristic matted appearance. This rock 

 is seen in the canal to within 9 miles of Fort Lauderdale (52 miles 

 from Lake Okeechobee). 



The following is an analysis of a sample of this rock from the 

 North New River canal, 13 miles from Fort Lauderdale. 



Analysis of limestone from the North New River Canal. 



Per cent. 



Calcium oxide, 39.88%, equivalent to calcium carbonate 71.23 



Magnesium oxide. 0.20%, equivalent to magnesium carbonate 0.40 



Phosphoric acid trace 



Insoluble, silica, etc — 26.56 



Lying upon this limestone is a stratum of sand which was cut 

 across in this canal for about 3 miles, or from 52 to 55 miles from 

 Lake Okeechobee (9 to 6 miles from Fort Lauderdale), where it 

 passes beneath the Miami oolitic limestone. This latter formation, 

 the Miami oolite, coming in- on this canal just above the dock 

 extends east to the Atlantic Ocean. The following analysis was 

 made from a sample of this rock from the North New River canai, 

 4 miles from Fort Lauderdale. 



Analysis of Miami Oolitic Limestone. 



Per cent. 



Calcium oxide, 42.40%', equivalent to magnesium carbonate 75-73 



Magnesium oxide, 0.09%, equivalent to magnesium carbonate 0.18 



Phosphoric acid trace 



Insoluble, silica, etc 23.00 



A word as to the substructure of the Everglades is of impor- 

 tance in this connection since from the underlying formations 

 must be obtained the water supply so necessary to the development 

 of the country. As already indicated the Pliocene deposits seen 



4 



