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You'd think Mama had never seen a phone. She makes no allowance for science. She thinks she has to cover the distance by sheer lung power.
— Ann Newton

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker jokes about their mother shouting into the phone as if it couldn't carry her voice. She ignores what technology can do and assumes she must project across the distance by sheer lung power. It's an affectionate, exasperated portrait of old habits.
Context reviewed