The Gutenberg Rubric

Did Gutenberg leave a secret? Just months before the famous Bible that bears his name was finished, Johannes Gutenberg was sued by his partner for misappropriating funds to a private enterprise. When Gutenberg refused to share the secret project, the court awarded the entire Bible-printing operation to Johan Fust, leaving Gutenberg with nothing but his secret. Was it an alchemical formula? A new technology? A heretical treatise? Or something far more dangerous? Why would Gutenberg sacrifice...