When Hitler continued his aggression, Chamberlain pledged Britain to defend Poland's independence if the latter were attacked, an alliance that brought Britain into war when Germany attacked Poland in 1939.
FIND OUT MORE. The Earth is covered in a layer of solid rock called the crust. Rocks are either SEDIMENTARY, IGNEOUS, or METAMORPHIC. Almost all rocks made of minerals, but different rocks contain different mixtures of minerals.Granite, for example, consists of quartz, feldspar, and mica.IND OUT MORE. The Earth is covered in a layer of solid rock called the crust. Rocks are either SEDIMENTARY, IGNEOUS, or METAMORPHIC. Almost all rocks made of minerals, but different rocks contain different mixtures of minerals.
Structure of the Earth. The Earth is made up of many rocky layers. The solid, outer layer is called the crust. Below the crust lies a layer of very hot, almost solid rock called the mantle. Beneath the mantle lies the core. The outer core is a liquid mix of iron and nickel, but the inner core is solid metal. Sometimes, hot molten rock, called magma, bursts through Earthâs surface in the form of a volcano.