My upcoming book on Invisibility includes an Invisibibliography of all the invisibility stories I found before finishing the draft. As the following story indicates, there are still more to be found…

I am amazed that I can still find even more science fiction and horror stories about invisibility, even after I’ve researched for hours! My most recent discovery is “Valley of Invisible Men,” by Edmond Hamilton, that appeared in the March 1939 issue of Amazing Stories. The lead pages of the story are shown below.

This story is a rather standard “lost world” type adventure, where a daring protagonist ventures into dangerous unexplored lands, meeting hostile natives, falling in love, and encountering lost technology!

The story is written by Edmond Hamilton, a classic author of pulp science fiction stories. Though I’m not sure people today are very familiar with his work, he was incredibly prolific and had a significant impact on the science fiction genre. He also wrote a lot for DC Comics, starting in 1942, in particular focusing on Superman and Batman stories. Oddly, people are probably most familiar with an image from his story “The Clash of Cape and Cowl” in World’s Finest Comics #153, which spurred a stunningly famous internet meme:

Valley of Invisible Men begins with American agent Mark Bradford crashing his airplane on a remote and unexplored Brazilian plateau. He has been sent on a mission to uncover the secret of “The Shining God,” a tribal artifact that is supposed to be able to turn anything invisible! He needs to secure the artifact before the unscrupulous “Baltic Empire” agent Hogrim can get his hands upon it.

After escaping the wreckage, Bradford heads towards a large lake with an island in the middle, but finds himself stalked by an invisible jaguar! Very visible natives arrive just in time and throw a net over the jaguar and capture it, but this is little reprieve for Bradford — the members of the Krimian tribe are hostile and take him prisoner. Brought before their kind, he gets an unpleasant surprise: Hogrim is already on the island, and has allied himself with the Krimians to secure The Shining God, held by the people of Korlu on the island in the lake.

Bradford is thrown into a cell, and finds himself in the company of Krellis, an English agent, and Moreau, a French agent, also on a mission to seek The Shining God. But the biggest surprise is that the cell also holds an invisible woman — Lua, a member of the Korlu tribe that had been captured.

The people of Korlu are peaceful and have kept to themselves for generations, using the power of invisibility they discovered to repel the violent Krimians. But now Hogrim has a plan to thwart their invisibility, and this might mean not only the destruction of Korlu but also the subjugation of the world to the Baltic Empire! Can Bradford and his allies defeat Hogrim and the Krimians and secure the power of invisibility themselves?

From there, the story is pretty standard, albeit fun, pulp adventure fare. There are twists and turns, and Lua and Bradford fall in love, and eventually good wins out. Also rather standard for pulp stories of the era, there’s a noteworthy amount of racism in the story, as Lua explains as she tells her tale:

“It was the attacks of the Krim, the barbaric brown warriors from outside, that long ago drove us Korlu to refuge of invisibility.

“We Korlu,” she continued, “are a white race, not brown like the Krimians.”

Yikes. It wouldn’t have been hard, Edmond, to leave skin color out of it entirely!

But how is invisibility achieved? Hamilton is rather imaginative in this. The Korlu have discovered a massive radioactive stone, whose emanations gradually turn anything exposed to them invisible. This is very much similar to how, when X-rays were discovered, people automatically associated X-rays with invisibility, so much so that H.G. Wells used mysterious rays as a recipe for his own Invisible Man.

Hamilton’s description of invisibility is intriguing:

“I can’t understand it,” Mark told the others puzzledly. “The scientists who examined that invisible arrowhead from Trask’s body said that it was invisible because the frequency of vibration of its atoms had been stepped up to such a point that light-rays slide between the atoms of it.”

Crellys nodded. “That’s the secret of this invisibility—an increase in the pitch of atomic vibration. The Shining God, whatever it is, is undoubtedly the source of some energy that can cause such an increase in atomic frequency.”

The premise seems again related to X-rays. Just as X-rays are of such a high frequency that they can pass through almost anything unobstructed, Hamilton imagines the reverse: The Shining God’s rays up the frequency of vibration of the atoms to a level where ordinary light just passes right between them.

The reason that Bradford is puzzled, though, is a common invisibility conundrum: if Lua is invisible, so are her eyes; how can she see? Hamilton attempts to explain this as well:

“But if the light-rays slide between the atoms of Lua’s eye-retinas, how can she see?” Mark demanded.

“I never thought of that!” exclaimed Moreau.

“I have,” Peter Crellys said thoughtfully, “and I think I understand the reason. The light that slides between the atoms of the retinas is able to induce a reaction in their sensitive substance, just as one charged wire can induce a current in another without actual contact. So these Korlu are able to see.”

This is an intriguing appeal to electromagnetic induction, discovered by Michael Faraday and which I’ve blogged about before. In short: Faraday discovered that a changing magnetic field, such as that produced by a changing current in one wire, can induce a current in another wire. This was one of the major discoveries that led to the understanding that electricity, magnetism and light are all related.

The end of the story is surprisingly positive. Bradford manages to save the Korlu, and the Korlu in turn agree to give him a small piece of The Shining God (which is massive) for him to take back to study. When he returns to America, President Roosevelt vows to keep the power of invisibility secret, only to be used in a dire emergency,

One last thing is worth mentioning: the story has an awkward typo in one action scene, and it caused me much confusion and hilarity the first time I read it! I’ll leave it to the reader to spot what’s odd about this passage: