In the course of your research, you have made a number of Discoveries regarding the nature of alchemy. You gain one Discovery of your choice from the "Discovery Options" section later in this class's description.
You gain another Discovery at Alchemist levels 9, 13, and 17. You can't pick the same Discovery more than once. Whenever you gain an Alchemist level, you can replace one of your Discoveries with another one for which you qualify.