Hmmm, the wording is interesting; Abby tells Dr. Bowen that she is afraid she has been poisoned, like she almost means that she has accidentally done it to herself and not that someone has been poisoning her?
From Dr. Bowen's Inquest testimony, pg. 115:
Q. You had not been called that week to the family?
A. No Sir, I had not been called. I went over to see them. The day before, Wednesday morning, about eight o'clock, or before eight, Mrs. Borden came to the door and said she was frightened, said that she was afraid she was poisoned. I told her to come in. She sat down, and she said the night before about nine o'clock she and her husband commenced to vomit, and vomitted for two or three hours until twelve, I understood.
Q. What morning was this?
A. Wednesday morning. I asked her what had she eaten for supper, and she told me. She said she had eaten some baker's white bread, and she had heard of baker's cream cakes being poisonous, and was afraid there was something poisonous in the bread that made her vomit. She said she only ate cake and baker's white bread. At that time she had a sort of an eructation of vomitting, slightly. I was afraid she was going to vomit there, I rather got ready for her. I told her to go home, and told her what to take; and she took it.

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