228 NEW YOKK STATE MUSEUM 



Oxide of iron 3.72 



Alkalies 8 . 85 



Water 7.4=9 



101.62 



"We give here an analysis of the shale at Lyth's yards : 



Silica 65.15 



Alumina 15 . 29 



Oxide of iron 6 . 16 



Lime 3.50 



Magnesia 1.57 



Alkalies 5 . 71 



97.38 



J. Lyth & Son also manufacture hollow brick and terra cotta 

 lumber. 



Rochester. Otis & Gorsline use a mixture of New Jersey 

 fire clay and a quarternary clay obtained from Chili near Roches- 



Circular down-draft kiln for tiles, etc. 



ter. The method of manufacture followed by them is very simi- 

 lar to that at Angola. Rectangular , kilns are however used for 

 burning, which takes about one week. 



Sewer pipe are also manufactured at Albany and Troy but from 

 New Jersey clays. 



