Dilo and the Witch of Black Rock is the 4th book in a series of books by Horace Dobbs about a fictional dolphin named Dilo for children aged 6 - 12, although from the mail Horace receives, it is obvious that they are enjoyed by readers of all ages. All four books (Dilo and the Call of the Deep, Dilo Makes Friends, Dilo and the Treasure Hunters and Dilo and the Witch of Black Rock) are all available in hard copy as paperbacks from the Dolphin Shop