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NEW YORK STATE MUSEUM 



and very plastic, but tough in places. The lower portions are 

 quite free from sand. Mr. Meyers claims a thickness of at least 

 25 feet of clay in addition to the 10 feet exposed. At the 

 entrance to the pit the clay is seen to be underlain by a bluish 

 white micaceous sand, which is cross bedded and dips under the 

 clay at a very steep angle. Hauling the clay is done in carts, 

 and tempering in ring pits with the addition of sand and coal 

 dust. Soft mud machines are used, and the drying is done on. 

 palettes. The pallet racks have sectional roofs which are hinged 

 and can be lifted by a lever for the purpose of admitting more 

 sunlight. The bricks are burnt with wood in clamps, and the 

 product is shipped to various points on Long Island. 

 Below is given an analysis of the lower clay : 



Silica 62.39 



Alumina 23.60 



Oxide of iron 3 . 39 



Lime , . . 



Magnesia . 1 



Alkalies 5 . 89 



96.07 



The low percentage of lime and magnesia would make this 

 clay available for a higher grade of clay product, such as terra- 

 cotta or pottery, but the high percentage of alkalies is somewhat 

 objectionable. 



Staten Island has two yards where common brick are manufac- 

 tured. One of them belongs to McCabe Bros, at Green Ridge. 

 Their deposit is a stony glacial clay of a red color, and lies to 

 the northwest of the yard. Small boulders are scattered spar- 

 ingly through it, and the upper portion is somewhat loamy. 

 Borings have penetrated the clay to a depth of 25 feet and strati- 

 fication appears with the depth. JSTo sand or coal are added to 

 the clay in tempering. It is first passed through rolls two feet 

 in diameter, the one making 60 the other 600 revolutions a 

 minute, and having an opening of half an inch. This partially 

 breaks up the stones. The crushed material falls on a belt and 

 is carried up to a pug mill where the water is added before it 

 passes to the machine. Drying the bricks is done either in the 

 sun or in tunnels. In the latter the bricks shrink more. The 



