Yet another invisibility story! It is simply amazing how many of these are out there. And I haven’t even really looked past the year 1960.

If you look at the cover of the January 1927 issue of Amazing Stories, you could be forgiven for thinking that it contains a reprint of H.G. Wells’ classic The Invisible Man — I mean, Wells’ name is right on the cover!

That cover image, however, depicts a scene from a different story, “The Man Who Could Vanish,” by A. Hyatt Verrill, which is our next invisibility story to discuss!

A. Hyatt Verrill appears to have been quite a curious figure. He was not only a prolific author of fiction and non-fiction but also a zoologist and explorer! He wrote a stunning number of books on natural history with titles such as Strange Birds and Their Stories (1938).

“The Man Who Could Vanish” is a rather straightforward and silly example of invisibility fiction. It is written from the point of view of a nameless narrator, who describes in a somewhat cynical manner the experiments of his friend, Dr. Lemuel Unsinn, Professor of Physics at “Stanforth University.” These experiments culminated in an entire building disappearing for a minute in full view of the public, and now that time has passed the narrator feels it is safe to explain the whole incident.

Lemuell has, of course, nearly perfected a method of making a person invisible. I say “nearly” perfected, because in his first meeting with the narrator he has not yet figured out how to turn inorganic matter invisible, which is why his glasses, buttons, and other objects are plainly visible in the cover illustration! He soon remedies this and asks the narrator to accompany him on a trip through town, so that he can assess the effectiveness of his invisibility and the effect it might have on the general public. Of course, hijinks ensue and Lemuell at one point finds himself carrying a woman in a crowded square, to the shock of onlookers!

Honestly, not a whole lot happens in the course of the story, and it ends with the Professor vowing to present his discovery in secret to the government in case of emergency. The story itself is clearly intended to be lighthearted, but I found the very hostile and unscientific attitude of the narrator removed a lot of the charm:

“For Heaven’s sake!” I cried, “Don’t do that. I’ll have a nervous collapse if that disembodied voice of yours keeps on.”

The voice laughed, but the next instant my friend was before me as substantial as ever. “You’ll get accustomed to the sensation,” he declared, “but—”

“Never,” I broke in. “No normal person could ever get accustomed to seeing a man vanish before his eyes or to hearing a voice talking from thin air.”

“Hmm, I had rather expected something of this sort,” admitted Lemuel. “No doubt it is a bit unnerving but you must accustom yourself to the phenomenon. Now, if you will follow my directions and, using a duplicate instrument, will render yourself invisible—”

“I will not!” I declared. “I have no desire to try the experiment. But even if I did I fail to see how that would render your disappearance any less uncanny.”

The narrator of the story must be one of the only people in the history of the human race who wouldn’t jump at the change to become temporarily invisible, if only out of curiosity!

The plot of the story is thus rather irritating, but the description of invisibility is a new one to me, and surprisingly clever!

As you, my friend, are deplorably ignorant of higher physics, I may perhaps better explain the process by comparing it with certain phenomena of radio with which you may be more or less familiar. Do you know the meaning of the term ‘heterodyne?’ ”

I nodded.

“Good,” continued Lemuel. “Then I can state that by my process I send out certain vibratory waves from my apparatus, and these, striking the light rays, reflect them back with a frequency which renders them invisible. In other words, the light rays which would, normally, strike a solid object, and, being reflected therefrom, would cause that object to become visible, are prevented from striking that object by my method, but strike an armor of an envelope of outgoing vibratory waves. Is that clear?”

When I read the word “heterodyne,” I was suddenly paying attention! “Heterodyning” is a process by which two oscillating signals of different frequencies are combined to make an output of a different frequency. That is, if we call the frequency of the input signals A1 and A2, then the output could be, in the simplest case, a combination of signals at frequencies A1+A2 and A1-A2. Below is a schematic illustration of the idea from Wikipedia: an input signal is mixed with a local oscillator to produce the output.

Heterodyning was invented by Reginald Fessenden in 1901 as a method to make audible those signals used at the time in radio telegraphy.

So how does heterodyning make something invisible? Verrill imagined an invisibility device that is constantly giving off a vibratory signal in all directions. Then any light scattering from the invisible person gets its frequency shifted by the vibration. The frequency of light determines its “color”; Verrill imagines the invisibility device pushing the frequency of incoming light either into the infrared or ultraviolet region of the spectrum, out of the range of human sight!

This is a really neat science fiction idea. We have seen plenty of stories that assumed monsters were of an infrared or ultraviolet “color,” but here we have a hypothetical scheme for changing the color of the light reflected from the invisible person. It even comes with a built-in limitation: the person would be highly visible if looked at with an infrared or ultraviolet sensor!

This scheme would, however, simply make an object perfectly black, as no visible light would be reflected from it. Verrill recognized this and vaguely argued around it:

“You’d have a black object instead of a colored one,” I laughed.

“Exactly,” agreed my friend quite unperturbed. “Provided the absorption was imperfect,” he added. “But,” he continued, “if the means were such as to cause perfect absorption, in other words to allow the light waves to pass through the object, then it would become invisible, just as clear glass is invisible, even though glass reflects certain waves of light which cannot be detected by the human eye.”

It’s not clear exactly how Verrill imagines light waves being allowed to “pass through the object,” but it’s nice to see that he at least recognized the issue in his story! It looks like he’s implying that the light passing through the human body is heterodyned to a frequency where the body is transparent, and then frequency shifted back to the visible range when it exits the invisibility region? However, since the obvious types of waves that pass easily through the human body are X-rays, this could be a very unhealthy form of invisibility!

Of course, it is not — as far as I know — possible to make an object that heterodynes incoming light from all directions, but it is worth noting that heterodyning is used in optics to make very sensitive optical detectors.

So overall, Verrill’s story isn’t a particularly exciting one, but it does introduce a truly unique method of making something invisible! You can read the story here in pdf form.

It’s perhaps worth noting that other people apparently found Verrill’s yarn more entertaining than I did — it was also featured in the 1927 Amazing Stories Annual, which featured no less than three stories involving invisibility! More on those other stories in an upcoming post.