I've never seen anything like it. It feels more like magic than technology.

[ Riza sighs. She thought she had a good grasp on this stuff, but telephones and radios are much different than this sort of thing, aren't they? As Ed asks his question, her gaze slides back towards him from the gravestones. ]

Yes. My father.

[ She isn't sure how much to reveal regarding her father or his research to Edward. It's a secret that she's kept close to her chest, but then it wouldn't be a surprise to know that she and Roy had been close for a long time, would it? ]

He's the one who researched and developed Flame Alchemy.