Well most of the historians already agreed that the, "Sea Lion", would have failed anyway because of the weakened German Sea Power. Which was also compared to the, "Royal Navy".
It could then deploy when, or if, the Germans launched an invasion. Most historians agree Sea Lion would have failed regardless, because of the weaknesses of German sea power, compared to the Royal Navy.
The Song Dynasty was responsible for inventing and perfecting the first movable type printing press! I hope this helped you in what you were looking for.
