If you look closely at the image: Noah's father "Lamech" lived and maybe able to talk to Adam himself..
And Noah was able to live to see Abraham..
See.. If Adam wrote part of the Genesis, He can give the information to Abraham, then on and on.. to Moses..
How can "The Bible" information be not preserved when the writers of the Bible itself lived to see and talk to each other.
The Bible Writers are First Hand Experience, the people who went through the times wrote it.. So The Bible is a Fact..
By the way I'm still sick and tired of Priests saying don't interpret it literally. It is clear as day as stated.