I found this in the Technical Museum in Berlin. Roger Bacon is quoted as saying that it will be possible to make flying machines in which humans can sit.They will have artificial wings, like a bird in flight. Either perceptive or lucky for 1285. I visited his memorial in Oxford last October and wrote a post about it. Since then, the Westgate car park has been demolished to extend the shopping centre. I hope they preserve the memorial. The site is a mess at the moment.