The Metal Monster by Abraham Merritt

The Metal Monster is a fantasy novel by Abraham Merritt. It was first serialized in Argosy All-Story Weekly in 1920 and features the return of Dr. Goodwin who first appeared in The Moon Pool. The story starts with a foreword where Merritt is assigned the duty to relay Dr. Walter T. Goodwin's incredible tale of his encounter in the Trans-Himalayan mountains to the world, to let everyone know the terrible fate Goodwin's group barely escaped from and the possibility of other such monsters out there.