GLOSSARY. 
Granite, An un stratified rock, composed generally of quartz, 
feldspar, and mica, and it is usually associated with the oldest of 
the stratified rocks. 
Graywacke Grauwacke. A group of strata in the transition of 
rocks ; but the term has been so indefinitely applied, that other 
names will probably be substituted. 
Greenstone. A trap rock, composed of hornblende and feldspar. 
Grit. A coarse-grained sandstone. 
Gypsum. A mineral, composed of sulphuric acid and lime, 
and extensively used as a stimulant manure, and for making 
stucco and plaster casts, &c. It is also called Plaster of Paris. 
H. 
Hornblende. A mineral of a dark green or black colour, and 
which is a constituent part of greenstone. 
Hornstone. A silicious mineral, approaching to flint in its 
characters. 
L 
In Situ. In their original position where they were formed. 
L. 
LamincB. The thin layers into which strata are divided, but 
to which they are not always parallel. 
Lacustrine. Belonging to a lake. Depositions formed in an- 
<5ient as well as modern lakes, are called lacustrine deposites. 
Landslip. It is the removal of a portion of land down an in- 
clined surface. It is in consequence of the presence of water 
beneath, which either washes away the support of the superin- 
cumbent mass, or so saturates the materials that they become a 
slippery paste. 
Line of Bearings is the direction of the intersection of the 
planes of the strata with the plane of the horizon. 
Lignite. Wood naturally carbonized and converted into a kind 
of coal in the earth. 
Littoral. Belonging to the shore. 
Loam. A mixture of sand and clay. 
M. 
Mural Escarpment, A rocky cliff, with a face nearly vertical 
like a wall. 
Mammillary. A surface studded with smooth small segments 
of spheres like the swell of the breasts. 
Mammoth An extinct species of the elephant. 
Marl. By this term an argillaceous carbonate of lime is 
usually implied. By custom, its signification is much more ex- 
tended, and means mineral substances, which act as stimulating 
or fertilizing manures. There are clay marls, shell marls, and 
various others. 
