The pig Habeas Corpus first shows up in The Phantom City. Monk buys it from an Arab trader in Bustan where Doc and his crew are chasing down the villain Mohallet. Supposedly the animal was making a nuisance of himself by dragging up too many dead hyenas in front of his master’s tent
This thought first crossed my mind when I picked up book for my daughter, one I had read as a child. It was Freddy the Detective by Walter Brooks. If you’re not familiar with these stories, Freddy the Pig was a pig that wanted to be a detective and had all kinds of adventures around the farm.
The first Freddy book was published in 1927 with other books following in 1930 and 1932. Additional books followed but these were after the first appearance of Habeas Corpus. Freddy appeared in a total of 26 books published between 1927 and 1958. We don’t know the exact motivation Dent had to add a pet pig to the Doc Savage stories but it is not beyond reason to wonder if Lester Dent was tipping his hat to fellow author Walter Brooks while adding some humor to his stories.
A new character joins the Doc Savage crew in Dust of Death (October 1935). Ham encounters a small tailless ape in the jungle around Santa Amoza. After the ape attacks Monk’s pet pig Habeas Corpus with a stick, Ham instantly decides to keep him as a pet. Just as Monk has named his pet pig as an irritant to Ham, so Ham returns the favor.
Chemistry the what-is-it was not the only pet monkey of note. Before Chemistry there was Tarzan’s monkey friend, Cheetah the chimpanzee. Cheetah is probably the most famous ape of all time. Or perhaps second most famous, with King Kong coming in first. The Tarzan movies were immensely popular during this era. Cheetah made his first appearance in Tarzan the Ape Man in the 1932 movie. Cheetah was a familiar character to those going to see Johnny Weissmuller as Tarzan of the Apes. His next appearance was Tarzan and His Mate in 1934. Technically, Cheetah made an appearance in name only as a human in a monkey suit portrayed him.
Reader opinions about the pets vary but generally it seems less is more.