The dots thing does seem labor intensive. Hard to believe he did that by hand. I'm sure there's some digital way to do it today!
It would be hard to digitally do it and get the same effect. Finlay never let the pen nib touch the paper. He held the nib above the paper and the ink would drop, one drip at a time. His method was laborious, but created a beautiful effect. The drops were never uniform, so computers would have a hard time duplicating.
That seems hard to believe!
This passage from the Book of Virgil Finlay is not only a testament to the skill of Finlay, but a testament to how little you know!