200 GE1STEEAL GEOLOGY. 



free from silicious impurities, that they are readily sawed into 

 all desired forms for building purposes, by machinery erected 

 there for the purpose. Some of the layers as before mentioned 

 are finely veined by per-oxyd of iron, and are wrought into 

 beautiful table tops, mantels, and other ornamental and 

 useful objects. Without wishing to under estimate the real 

 value of this stone for such purposes, which is very great, it 

 is, nevertheless, proper to say that the hardness of none of it 

 is equal to that of real marble, and consequently its polish 

 cannot be expected to endure so long when exposed to the 

 weather. Therefore, it is not so well suited for monuments 

 and other similar purposes as true marble is, but no valid 

 objection can be raised against its use in the walls of the 

 most important buildings. The analysis of this rock may be 

 found in Prof. Emery's report in volume two. 



In Tama* county the oolitic member is well exposed at 

 several places where it is quarried and used for the manufac- 

 ture of lime of excellent quality. It has been proposed to 

 manufacture this oolitic stone into table-tops, mantels, etc.; 

 but although it may be made to receive a fair polish and its 

 oolitic structure gives it considerable beauty, it is feared that 

 the well known tendency of all oolitic limestones to become 

 fragmentary will be found to render it worthless for such 

 purposes. However, that near Orford and Indiantown 

 promises to prove valuable for such uses. 



This tendency of oolitic limestone to become fragmentary 

 has been very often shown at Burlington, where stone from 

 the oolitic bed there has frequently found its way into build- 

 ings and street improvements. Upon exposure to the 

 atmosphere and frost, it sooner or later crumbles to pieces, 

 and must be replaced by more durable stone. At Burlington, 

 where good stone is abundant, this oolitic stone should be 

 wholly rejected for all purposes except for lime, and in walls 

 that are never wet; and the citizens should not allow them- 

 selves to be deceived by the fine appearance of it when first 

 quarried. 



Fossils. The remains of fishes are the only fossils yet 



