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of lime arranged in a stellular manner, are sometimes 

 found. This latter mineral no doubt derives its origin 

 from the decomposition of the iron ; the sulphuric acid 

 produced, readily uniting with the lime contained in the 

 clay, would speedily accomplish this effect. In some situ- 

 ations where magnesia prevails as an ingredient, epsom 

 salts in acicular crystals has been the result, and was pro- 

 duced in all probability by the same chemical agency. 



In one of those thin seams of fine sand that separate 

 the strata of clay, about fifteen feet beneath the surface of 

 the soil, is to be found the remains of a vegetable much 

 resembling in appearance the leaves and stems of the 

 Mitchella repens, which now thrives most luxuriantly all 

 over the surface of the pine plains in this vicinity. These 

 leaves have undergone but a slight degree of change in 

 their nature, still retaining all the flexibility of the more 

 recent plant. This is the only instance of an apparent 

 fossil remain having been found connected with this for- 

 mation in the neighborhood of our city ; but Professor 

 Emmons has procured, from what he considers as equiva- 

 lent to its upper layers, along the shores of Lake Cham- 

 plain and the St. Lawrence river, many feet above the 

 reach of the tidal wave, the fossil remains of marine shells 

 that still have an existence along the shores in the neigh- 

 boring seas, together with some few that belong to the 

 waters of a more boreal or arctic region. The only ready 

 method to account for the paucity of fossils in this depo- 

 git, extensive as it appears in this section of country, is, 

 to consider it as having derived its origin from the waves 

 of a deep inland estuary or arm of the sea, with numer- 

 ous streams of fresh water continually discharging them- 

 selves into its basin ; by which means the water would 

 goon become too brackish for animals from the land, and 

 much too fresh for those belonging to the sea. 



Fibrous rootlets of plants, still retaining all the charac- 

 ters of a more recent vegetation, are to be observed in al- 



