If lost or destroyed, a new copy can be obtained from the bookcase in your Player-Owned House made through Construction.
Obtaining this text is a requirement for the Master quest cape. See Tips and Tricks to obtaining the Master Quest Cape for assistance obtaining the Master quest cape.
Below is the text you can read from within the book.
I saw Archy again but only out of the corner of my eye. I turned to look and he was gone, like he'd just vanished into the shadows. He looked strange, like he was wrapped in bandages. Horrible, filthy bandages caked in blood. They were billowing around him like they were caught in a breeze, but there's no wind in here, no airflow.
There was something wrong with his hands. I swear they glinted in the torchlight, long and metallic. What's going on here?
Saradomin save us, I saw Archy properly this time. The bandages that wrapped around him, they aren't bandages. I don't know what they are, but they were crawling over him, growing over him like some sort of horrible second skin. He was screaming the whole time, but one of them was growing over his throat, silencing him.
His hands were claws, huge metallic claws.
I think he was trying to call us to help, but the horrible flesh, that crawled all over him, dragged him back into the shadows. Controlling him like some nightmare puppeteer.
Now Adelunth has gone as well.
Sometimes I think I hear him whimpering for help, begging and pleading from the shadows somewhere.
I want to go home.