The word "seen" is a participle, not the present or past form of the verb "see". It cannot be used by itself as the verb of a sentence.
The word "saw" is the past form of the verb "see"; it is properly used as the verb of a sentence. Thus the correct sentence is:
- I saw her take the apple.
"I've got a message in a bottle, written in gas and oil, signed with a rag and a match"