xvi TABLE OF CONTENTS. 
Page. 
Overlies drift deposits... 126 
Description of sand beds and concretions. 126 
Lumps of clay in sand beds. 126 
Boulders on sand beds. 126 
Section at Montauk point. 126 
Gravel and pebble beds. 126 
Clay beds, marly. 126 
Some described by Dr. Mitchill. 126 
{b). Topographical and agricultural characters. 127 
Undulating plains, deep ravines... 127 
High banks of quaternary, localities, terraces... 127 
Soil variable according to predominance of sand or clay. 127 
Sand plains, drifting sands, reclaiming... 127 
Clay, timber growth, fertilizers. 128 
Location of towns on the quaternary. 129 
Gravel beds of quaternary, localities.. 129 
(c). Range, extent, elevation, thickness, terraces. 129 
Extent over the country, forms patches in 1 st district. 129 
Localities of patches in 1 st dist. Hills form islands in these deposits, localities, 129 
Localities and extent of deep sand beds... 133 
Localities and extent of clay lands. 134 
Thickness at various localities, borings for wells. 134 
and description on New-York island. 134 
Terraces in Rensselaer county. 141 
{d). Economical applications. 141 
Pebble beds, paving stones... 141 
Sand for casting, glass, mortar, bricks, etc. 141 
Clay, bricks, pottery. 142 
(e). Phenomena of water and springs, valleys, slides, etc. 145 
Water, purity of; “ hard water, how improved .. 145 
Springs and water of Long island applied to milling. 145 
Water holes, depth of wells. 146 
Water at ocean level. 146 
May be obtained on beaches and spits. 146 
Under the drift deposits and above them. 146 
Artesian wells, where they may be bored with a prospect of success. 146 
Not generally successful in New-York. 146 
Reasons for this. I 45 
Water on salt marshes. 145 
Water impure beneath great cities. I 47 
Supplies of good water obtained. I 47 
Albany, Hudson, and Croton water-works. 147 
