Nearing the end of my run of posts about invisibility in fiction! Be sure to look out for my book on the history of invisibility physics next year!

One thing that is truly amazing about invisibility in fiction is how much more prevalent it is than I first thought. So many famous authors have tackled stories about invisibility, from Jules Verne to Jack London to Ambrose Bierce to A.E. van Vogt. The idea of invisibility really has a power to it that has inspired many.

With that in mind, here’s another famous author’s story about invisibility, featuring one of his most famous creations! Today, we look at “Invisible Men of Mars,” by Edgar Rice Burroughs, which appeared in the October 1941 issue of Amazing Stories.

Edgar Rice Burroughs (1875-1950) probably needs no introduction, but if he does: he is the author of the Tarzan novels, which began in 1912, and the John Carter of Mars novels, which also began in 1912.

“Invisible Men of Mars” is the last John Carter story published in his lifetime, and the final part of a four part series. In this series, John Carter, who has now been on Mars for many years, encounters his granddaughter Llana of Gathol in an abandoned city, and the two of them embark on a number of adventures while attempting to stop the Warlord Hin Abtol from taking over Barsoom (aka Mars). Some mild spoilers provided, so as before read the story here first.

“Invisible Men of Mars” picks up where the previous story in the series left off: Carter has rescued Llana from the clutches of Hin Abtol, and now the two of them decide to fly their ship to the capitol city of Helium, to prepare a fleet to defend against Abtol’s forces. As often happens in Burroughs novels, however — and he often self-consciously jokes about it –the pair opt to make a small pit stop in an unfamiliar forested region for food. While Carter scrounges, his flying ship takes off without a pilot, stealing away Llana! Then Carter himself is overpowered by a collection of invisible warriors, who march him to Invak, their city, to face the judgment of their jeddak (leader).

As they travel, Burroughs humorously points out part of the problem of being part of an invisible patrol of men:

In front of me and behind I continually heard voices berating other voices: “Sense where you’re going, you blundering idiot,” or “Stop stepping on my heels, you fool,” or “Who do you think you’re bumping into, son-of-a-calot!” The voices seemed to be constantly getting in one another’s way. Serious as I felt my situation might be, I could not help but be amused.

In Invak, Carter is made a prisoner. The invisible people do not recognize him, so he uses his Martian pseudonym Dotar Sojat to keep it that way. In the city, he is chained up to await judgment, and makes several allies: a sympathetic soldier, a fellow prisoner, and a beautiful young woman who falls in love with him. He must use his wits and his fighting prowess to plan an escape before he is executed and his granddaughter is married off to a noble of Invak against her will…

Burroughs doesn’t dwell long on the science of invisibility, only spending time to relate that it is a chemical process conveyed by a pill; this information will prove very useful for John Carter in his escape.

“They have developed something that gives them invisibility for perhaps a day; it is something they take internally— a large pill. I understand that they take one every morning, so as to be sure that they will be invisible if they have to go outside the city. You see it takes about an hour for the stuff to work, and if the city were attacked by an enemy they’d be in a bad way if they had to go out and fight while visible. They are also working on a mechanical way to make themselves invisible, to eliminate the waiting period while the pills take effect.”

You might think that it would be very inconvenient to live in a crowded city where everyone is invisible all the time; fortunately, Burroughs thought of that, too:

“How do you do it?” I exclaimed. “It is very simple, but it is the secret of the Invaks,” he replied. “I may tell you, however, that we are invisible in daylight, or rather when we are not illuminated by these special lamps which light our city. If you will notice the construction of the city as we proceed, you will see that we take full advantage of our only opportunity for visibility.”

So in the city, they have special lamps that make them visible! Burroughs doesn’t explain it beyond this, but I could imagine it working something like a blacklight. Just as a blacklight can make certain materials fluoresce, or glow in the dark, one could imagine that the invisibility treatment also conveys a fluorescent reaction to some special sort of light rays.

“Invisible Men of Mars” is a surprisingly delightful story! Though Burroughs was already 66 years old when he wrote it, it comes across as fun as any of the original John Carter tales.

There are two things I love about John Carter in this story. First, he is portrayed as a truly honorable man. When the Invak woman Rojas falls in love with him, Carter genuinely struggles with the option to lead her on in order to escape with his life:

I have never loved but one woman — my incomparable Dejah Thoris; nor do I, like some men, run around pretending love for other women. So, as you say in America, I was on a spot. They say that ail is fair in love and war; and as far as I was concerned, I, personally, was definitely at war with Invak. Here was an enemy girl whose loyalty I could win or whose bitter hatred I could incur by my reply. Had I had only myself to consider I should not have hesitated, but the fate of Liana of Gathol outweighed all other considerations, and so I temporized.

In case it’s not clear from that passage: he would have been perfectly honest with Rojas and told her that he wasn’t interested if only his life was on the line, but since his granddaughter’s is also at stake, he ends up being evasive about his feelings for her.

The other thing I love about John Carter is his supreme American confidence which, coupled with his nobility, makes for quite a few entertaining scenes. When brought before the cruel leader of Invak, for example:

Ptantus looked at me so ferociously that I was sure he was attempting to frighten me. It seems to be a way that tyrants and bullies have of attending to break down the morale of a victim before they destroy him; but I was not greatly impressed; and, impelled by a rather foolish desire to annoy him, I stopped looking at him. I guess that got his goat for he thumped the desk with his fist and leaned forward across it.

“Slave!” he almost roared at me, “pay attention to me.”

“You haven’t said anything yet,” I reminded him. “When you say anything worth listening to I shall listen, but you don’t have to yell at me.”

The best scene, however, is the one that is featured on the cover of the magazine. Carter will almost certainly be put to death eventually, so as part of his escape plan, he challenges another of the cruel nobles of Invak, Motus, to a sword duel to the death. Motus is one of the greatest swordsmen on the planet — but he has not faced John Carter, and does not realize he is facing John Carter!

As a matter of fact I often realize that in speaking of my swordsmanship, it may sound to others as though I were bragging but really I do not feel that I am bragging. I know that I am the greatest swordsman of two worlds. It would be foolish for me to simper, and suck my finger, and to say that I was not. I am, and everyone who has seen me fight, knows that I am. Is it braggadocio to state a simple fact? As a matter of fact, it has saved a number of lives. For it has kept no end of brash young men from challenging me.

And the duel itself is one of the most entertaining I have ever read on paper! It is hard to imagine giving a perfect image of a Martian sword duel, but Burroughs does it magnificently. Carter makes a prediction to the cruel and egotistical Motus:

“You are tiring, Motus,” I said to him; “hadn’t you better finish me off now before you become exhausted?”

“I’ll finish you off all right, slave,” he came back, “if you’ll stand still and fight.”

“It is not time to kill you yet, Motus,” I said, glancing up at the clock, “when the hand points to eleven xats past the 8th zode, I shall kill you.”

And, of course, John Carter is true to his word!

If you’re only to read one John Carter story, “Invisible Men of Mars” is an excellent choice. Burroughs fills in the reader on the previous episodes of the adventure at the beginning, and because it is the final part of the series, the ending brings the entire saga to a satisfying conclusion — with invisibility playing a key role. It ends up being a great send-off for a legendary hero of pulp fiction.

The rest is history now — how Helium’s great fleet destroyed Hin Abtol’s fleet, and the army of Helium routed the forces which had for so long invested Gathol. When that brief war was over, we set free nearly a million of the frozen men of Panar; and I returned to Helium and Dejah Thoris, from whom I hope never to be separated again.