Sedimentary Rocks- sediments are made of sand and stones deposited by water, wind, or a glacier. Under pressure, the sediments form rocks.

Igneous Rocks- Rocks formed or made from molten rock that has hardened. Lava and granite are igneous rocks.

Metamorphic Rocks- rocks that are not in their original form – they have been changed by the forces of nature (heat, pressure, etc.)

Geology- the scientific study of the history and structures of the earth. Geologists study the layers of soil, rock, and minerals that make up the earth’s crust.

Revolutionary War- A war fought between America and the British in 1776-1781. The word revolution means a complete change in government or rule. In the American Revolution we gained independence from England.

Industrial Revolution- occurred in the late 1800s and continued into the 1900s. People left their lives as farmers in the country and moved to cities to work in factories to make more money.

Munitions- supplies for warfare, especially guns and ammunition.