imo it's not about the dialect, it's about how it was transcribed. Why not use original English spelling? You still keep the original meaning and grammar, the way the words were spoken by using correct spelling. Here I just replaced the D with TH, and corrected a few contractions: “We very sorry to be parted from one another,” Lewis told Hurston. “We seventy days cross the water from the Africa soil, and now they part us from one another. Therefore we cry. Our grief so heavy look like we can't stand it. I think maybe I die in my sleep when I dream about my mama.” On topic, his account is invaluable. I'm glad to hear about his story. Slavery seems to be too often forgotten or brushed away nowadays, or even being romanticised by far-right people. The horrible reality of being caught and brought forcefully to another continent to work as a slave, or being born and die as a slave should never be dismissed. It's part of the history of this country and should be taught properly.