I once went to a hastily arranged estate sale in a far end of the Valley, one for which little had been done save the opening of drawers, the scattering of material, and the posting of a sign. The result was a precarious landscape of stuff that sprawled and tumbled everywhere, jamming coasters with Parisian scenes up against humidifiers and pipe wrenches against books on television repair, the whole scene bathed in that filmy yellow only born of tungsten glow on brown paneling.

Such scenes are hardly happy; someone usually had to die for the occasion. But wading through the gloom sometimes pays off. For some people, that means ending up with a 1937 archtop guitar marked $10, but that isn't what I mean. Now and then, between some sandwich bag full of bolts and an electric putting machine, a real treasure lurks, some unexpected emissary from an idiosyncratic life, an outpouring of artistic fervor on canvas, or maybe a photo that evokes the past in luminous fashion. Sometimes piles of junk yield something so astounding it's terrible to think that it might have exited the world unremarked.

Such was the case around 40 years ago when a Houston man who restored old furniture made one of his frequent runs to the landfill in search of cast-offs to fix up. He spotted a truck dumping all sorts of things, and the flash of some brightly colored books caught his eye. When he recovered the books, he found that they contained a series of strange watercolors and collages depicting odd balloon-like machines in a style somewhere between hieroglyphics and colorful sideshow banners.

These handmade books turned out to be the early 20th-century work of a Houston man named Charles A.A. Dellschau, and the story they yielded is clearly a stunner of American ingenuity, one which pointed to a curious hidden history whose truth is doubtful, but not impossible. A new book, The Secrets of Dellschau, by Dennis Crenshaw in collaboration with P.G. Navarro, explores the story Navarro turned up in his exhaustive study of Dellschau's art.

As pure artworks, Dellschau's watercolors compel. Stripes criss-cross color fields, and the ornate renderings of impossibly awkward flying machines (with names like Aero Gander and even Aero Honeymoon) sit inside detailed borders, sometimes accompanied by text, collage, or press clippings (which Dellschau called "press blooms"). And indeed, in the days since the discovery of the books, many of the pages have been removed and sold, some of them fetching many thousands of dollars at auction.

But Navarro, who saw the first display of Dellschau's work in a Houston art exhibition soon after their discovery, felt so drawn to the books he spent endless hours poring over them in the shop of Fred Washington, the man who found them—Washington wouldn't sell them at a price Navarro could afford, but did allow Navarro to visit the shop and study them. In so doing, he turned up something startling: Dellschau had employed encoding of several kinds to hide a story in the pages.

Breaking the codes took significant work, but finally yielded an involved accounting of the activities of something called the Sonora Aero Club, a group of tinkerers with flying machines in the 1850s. On the face of it, the story is ludicrous, even involving an anti-gravity gas. Yet some of the drawings include components that appear to be both realistic and possibly workable. Put that with a famous incident in the history of the unexplainable—a rash of sightings in the late 1890s of airships of unknown provenance—and Dellschau's story gets even more compelling. The earliest of his works seem to be missing, and would likely cover the late 1890s, so that part of the story might yet get told. Perhaps some truth really does lie between those rich pages.

Crenshaw's book on Dellschau is an authoritative source, since it comes from many recollections by Navarro himself. That's the good news. The bad news for lovers of history is that the book, based though it may be on real events, consists of dramatizations of the search for knowledge about the enigmatic C.A.A. Dellschau. Those dramatizations are competently crafted, but are an odd fit with a work of history, even the highly personal history of an outsider artist. If you love such stories of homemade intrigue, of obsessive eccentrics (visionary loner Henry Darger seems to have been a kindred spirit) lovingly creating complex worlds whose relationship to reality is fuzzy, it's worth getting past the book's awkwardness to enjoy the particulars of a fascinating voyage of exploration that opened intriguing doors of possibility.

And the whole implausible but true tale will have at least one near-guaranteed effect: drive by a landfill in the Valley and you'll find yourself wondering just what lies buried there, what grand flights of idiosyncratic fancy we might have lost. And when you visit an estate sale, the urge to make certain you've explored even that dusty box in the corner might prove overwhelming."

The Secrets of Dellschau can be purchased at AnomalistBooks.com.