Our transcription: Lab work by Norman Bowen and other experimentalists has given us precise information about how magma crystallizes. Bowen called the sequence of mineral crystallization in magma a "reaction series". This is because as magma cools early forming minerals may react with the magma to form new minerals at lower temperatures. Some minerals react "continuously" with the magma, and so are constantly undergoing change. Others react "discontinuously;" that is, only at certain specific temperatures.
