I am losing my mind.

So: in the process of tracking down Rousseau’s The Invisible Death a few days ago, I learned that there is another story about invisibility, with almost the exact same name, Invisible Death, that appeared in the same magazine, Astounding Stories of Super-Science, earlier in the same year but by a different author, Anthony Pelcher. Rousseau’s tale appeared in the October 1930 issue; Pelcher’s appeared in the January 1930 issue.

Let me describe what happened next using my tweets:

The story I’m referring to will appear in yet another upcoming post! But then, I got curious, and started browsing more issues of Astounding, and…

And I kept looking, and it just kept getting worse!

So, to recap: while researching one invisibility story, I managed to find four more!

The moral of the story is that I’m somehow even more behind in my blogging about invisibility stories than I was yesterday, so let’s look at another tale! Tonight: we look at Raiders Invisible, by Desmond Winter Hall, that appeared in Astounding Stories in November of 1931.

In this weird war story, Lieutenant Christopher Travers must solve an invisibility-fueled conspiracy to wreak havoc on the United States!

The story begins with the United States Navy engaging in some wargames, with a scenario imagining the Panama Canal being attacked. Travers, a pilot for the “blue” team, tasked with “defending” the canal, launches from his base, dirigible ZX-1, in search of the “enemy.”

He tracks down the “black” team’s own dirigible, the ZX-2, when he sees, to his horror, the dirigible starts listing to the side. An unfamiliar aircraft detaches from it and flies away, and then the dirigible explodes in a fiery blast! This is particularly shocking because the dirigible was filled with non-combustible helium — this was sabotage, not an accident.

Travers turns to fly back to his home dirigible, to find it in similar distress. He recognizes the same unfamiliar aircraft docked to the ZX-1, and as he watches, the craft again releases and flies away — and it doesn’t appear to have a pilot! Travers docks himself to investigate, and finds the entire crew dead, victims of some sort of toxic gas. Furthermore, he finds a time bomb on board, and manages to toss it overboard just before it explodes and takes the ZX-1 with it!

Travers gets to the radio to call the fleet, and then…

Crack!

A gun barked out from behind; something crashed and splintered on the radio panel. Chris felt a white-hot needle sear along the side of his head. His brain reeled; with everything dancing queerly before him in splotches of gray and black he toppled down off the seat, knowing the radio-telephone had been put out of commission by the cessation of sound in the ear-phones clamped to him

He gripped his consciousness hard. It was like a delirium: he was lying sprawled beside the seat, twisted round so that he saw, hanging in the cubby’s entrance door, an automatic, dribbling a wisp of smoke—the automatic that had just fired, but hanging there by itself, held by something he could not see!

An invisible spy has boarded both dirigibles and murdered their crew, and now sets his sights on Travers! The heroic Lieutenant manages to drive off the attacker, who boards his plane and retreats towards his secret base. Travers follows in his own craft, and learns of a plot by the Soviets, using invisibility, to destroy the Panama Canal!

So how is invisibility achieved in this story? The Soviet spies monologue about it while they have Travers captured:

“See you, Kashtanov,” came Istafiev’s voice. “The refractive index, lowered to that of air to produce invisibility, iss being raised again—all through a simple adaptation of Roentgen’s theories! The substance above, mark, in the dome, which this morning you saw affect Zenalishin’s blood and the pigment of his hair so that the vibrations would render his colorless tissues transparent, iss now reversing. Soon—see!—already he becomes visible!”

Again a science fiction story uses Roentgen rays, i.e. X-rays, as a mechanism for creating invisibility! As we’ve discussed before, the ability of X-rays to see through objects seems to have been naturally interpreted by people as turning the objects invisible. The X-rays were interpreted as lowering the refractive index of the human body to that of air, so that light rays pass through the body without being reflected or refracted.

This is exactly the same set of mechanisms that H.G. Wells used in The Invisible Man to achieve invisibility, so Hall was definitely cribbing from Wells’ homework in writing his own story.

X-rays, of course, allow us to create images of the human skeleton, and skeletons make an appearance in the tale, as the invisible saboteur, now dead of his injuries, is de-invisibilized:

The effect was that of an X-ray. A skeleton hung in the cage, held steady by the cords around its arms, its naked skull with yawning eye-pits grinning out at the four men in the room. Soon other details became visible: black lumps that were organs, the web of fine thin lines that were veins; and then a hazy, ghostly outline of flesh that quickly assumed solidity, burying the bones and veins and organs which had been first apparent.

Overall, Raiders Invisible is a pretty typical pulp adventure story. There are twists and turns, improbable escapes, and implausible schemes. Not a very memorable tale, but noteworthy as yet another one that attempts to use “scientific” invisibility as part of its plot.