The author Mary Shelley use the word chimerical in that line because she said that the powers of Cornelius Agrippa were improbable and because she wanted to say this in a fancy way.
Hope this Helps :)
BTW, Mary Shelley is the author of Frankenstein <span />
An Active voice means that a sentence has a subject that acts upon its verb. Passive voice means that a subject is a recipient of a verb's action. You may have learned that the passive voice is weak and incorrect, but it isn't that simple. When used correctly and in moderation, the passive voice is fine.
Explanation:
Peeta is a strong skilled survivor who has been through a rough journey and is confused as how to cope with his own feelings