66 The Limestones, and Lime. [Feb., 



At the first view of the fact, the discovery at two distant points 

 of a limestone in the same formation, would be regarded as an 

 accident. We should not expect that in the workings of inor- 

 ganic nature, that the steady recurrence of one kind of mineral 

 matter would be likely to happen. But we find that the same 

 hand which has sown broadcast seed for the mountain, the valley 

 and the marsh, has also made the limestones to grow in their eras 

 and seasons. 



We shall describe the limestones as they are distributed in the 

 formations, beginning with the oldest or lowest, and thence we 

 shall proceed and speak of them in the ascending order. 



Limestone of the Primary System. — Few rocks possess a 

 greater interest than this, when associated with granites. Hence 

 it is in this particular association that we find a clue to an ex- 

 planation of several important facts; besides it overthrows an old 

 dogma that granite is the oldest and lowest rock upon the globe. 

 This is not, however, the place to speak of this matter; it will 

 receive attention under the general head, the origin of limestone. 

 Primary limestone is white, granular, and quite coarse-grained, 

 and is rarely pure or free from foreign minerals. It contains 

 mica, hornblende, pyroxene quartz, serpentine, and graphite. 

 The rarer minerals are chrondrodite, spinelle and sapphire. But 

 the most injurious one is silex, which is frequently disseminated 

 in fine or coarse particles, or seggregated in masses, in which it 

 is common to find imperfectly developed hornblende or pyroxene. 

 The presence of one of these minerals of course injures limestone 

 for all the purposes to which it is applicable, but usually in the 

 large beds comparatively pure masses occur, which may be se- 

 lected from the impure. 



Localities. — It is impossible, or rather it will be inexpedient, 

 to give all the localities of this rock which have fallen under our 

 own observation, or under the observation of others. The fol- 

 lowing, however, are some of the most important in the state of 

 New York, namely, Hammond, Rossie, Gouverneur, and Ant- 

 werp, which taken together constitute a region over which lime- 

 stone is widely spread, though not in continuous beds. It here 

 contains very frequently phosphate of lime in small and large 

 six-sided prisms, crystals of feldspar, pyroxene, and zircon, which 

 latter mineral seems to replace the sapphire of Orange county; 

 mica, and graphite, and quartz, are perhaps the most common 

 minerals. Graphite is usually in disseminated folia, but rarely in 

 veins. 



There is another limestone district in Edwards and vicinity, in 

 St. Lawrence county. Specular iron ore and carbonate of iron 

 is often associated with these beds. Theresa and its vicinity also 

 is another district where primary limestone is common, particu- 

 larly in the direction of Muscolunge lake, and upon its shores^ 



