STATE GEOLOGIST. 89 



It must be confessed that in lithological characters, these 

 rocks cannot be distinguished from strata of the Marshall 

 Group; and they are assigned to the Napoleon Group simply 

 in consequence of their occurrence at a higher geological level 

 than the highest strata, (those at Pt. au Pain Sucre.) which 

 contain Nucula and Clymenia. 



There is little doubt that some of the sandstones before refer- 

 red to, as occurring near the forks of the Cass river, should be 

 assigned a position in this group, but it is impossible with our 

 present knowledge, to draw dividing lines. 



The next outcrop of these rocks is found at Napoleon, in 

 Jackson county, where they are quarried over an area of 88 

 acres, and expose a section of about 15 feet. The rock is for 

 the most part of A grayish color, inclining to buff. The beds 

 are generally of sufficient thickness and perfection to answer 

 either for flagging or building. The following is the stratifica- 

 tion: 



4 Sandstone, buff and bluish-gray, composed of transparent 



and colored grains of quartz, thick bedded, 40 ft. 



3. Sandstone, yellowish, thick bedded 4 ft. 



2. Sandstone, thick bedded, pale greenish 20 ft. 



1. Sandstone, greenish buff, composed of minute rounded 

 grains of colored quartz pretty firmly cemented with 

 a very perceptible quantity of white calcareous mat- 

 ter 11 ft. 



The higher beds are worked on the grounds into excellent 

 window sills and water-tables, which sell for 28 cents per linear 

 foot. I saw some fine floated and • moulded stone steps and 

 door-sills, selling for 37| cts. a square foot. The rough stone 

 ■costs 25 cts. a perch at the quarries, or 50 cents a perch of 1600 

 lbs. on board cars. The charges for freight ar6 two cents a 

 hundred to Jackson, four cents to Adrain, ten cents to Monroe. 

 The quarries at this place furnished the cut stone for the new 

 Union School building in Monroe, also for the City Hall at that 

 place, and the Union School House at Tecumseh. A fine store 

 of this stone, with smooth front, has been erected at Hillsdale. 



Some beds of this stone are sufficiently clean and sharp to 

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