CRYSTALS, &c.

5.Octohedron.
6.Rough diamond.
7.Profile of a brilliant-cut stone.
8.Profile of a rose-cut stone.
9.Plane of a table-cut stone.
10.Plane and profile of the Pitt diamond.
11.Dodecahedron.
12.Rough garnet.
13.Six-sided pyramids, joined base to base.
14Regular four-sided prism.
15.Six-sided prism.
16.Cube.
17.Four-sided pyramid having a rhomb for its base.

PLATE III.

SECTION OF ROCKS.

I. Primitive Rocks.

Fig.
1.Granite.
2.Gneiss.
3.Mica-slate.
4.Clay-slate.
a. Lime-stone.
b. Quartz.
5.Primitive lime-stone.

II. Secondary Rocks.

1. Transition Rocks.

6.Grey-wacka.
7.Transition lime-stone.

2. Floetz Rocks.