Of course, the book of Enoch is not a part of the Scripture. The Hebrew word used in Isaiah 40 is chug - which can also mean circuit or sphere. This is one of the few places in Scripture that it is used. Although many may have believed the earth was flat - the Bible didn't say so. It was Christians who first posited the theory that the earth was a round sphere and then put their lives on the line by hopping in little boats and going out on the ocean to prove it. In fact, as you are probably aware, until the government schools of Europe and America became virulently anti-Christian in the 20th century, many advances in science in the prior 300 years was made by devout Christians.
Think about the context in that particular section of the bible including my comments about a tent trying to cover Australia and all of the other sections of the bible that describe the earth as being flat.
You obviously haven't been following the parts of the thread where we discuss the Greeks knowing about the sphericity of the Earth 200 years before Christ.