One of the greatest pleasures I got as a child was when I was taken with my parents to my father's insurance office. While he worked on his insurance policies, and my mother helped him, I was allowed to go down the street with a crisp one dollar bill in my hand. Which as a lot then!
I went to the local five and dime store and found the paperback books. Ace was publishing two novels for the price of one back then and if you were lucky...I was that day...then you would find their latest and scoop it up for a whopping 35cents. That left me after a penny tax enough money to buy a soda and candy to last the day.
I took the book I found that day, a back to back Edgar Rice Burrough's novel. At the Earth's Core and one other I don't remember now.
I was in hog heaven for the rest of what could have been a boring day as I read and read until my eyes were popping out about the brave souls who descended in this Victorian earth burrower that cut through rock and dirt to the Earth's Core.
And what they found were prehistoric beasts, sentient alien ones, and a primitive people with a beautiful princess.
Oh joy! What glory days those were.
Anyway, here's the first chapter of that glorious books, which though you can't hold it between your sweaty palms, you can let its squeeze between your ears and ooze into your brain, propagating it with visions of another world, time and space.