The Secrets of Dellschau

About the Author

Pete Navarro was a commercial designer and ufologist whose sustained work on the Dellschau notebooks is the substance behind this book. He identified the coded elements in the drawings, worked out the substitution scheme, and reconstructed the Sonora Aero Club narrative over a period of years — a genuine feat of amateur documentary scholarship on material nobody else had taken seriously.

Dennis G. Crenshaw is the credited principal author and the person who turned Navarro's accumulated research into a publishable volume. The title page describes the book as Crenshaw's in collaboration with Navarro, and the distinction matters: the decoding is Navarro's, the framing and argument are Crenshaw's.

That split is where the book's central tension lives. Navarro did the work and reached a sceptical conclusion; the book that presents his work is more interested in the possibility that the Aero Club was real. A reader has to keep track of which voice is speaking.

The publisher, Anomalist Books, is the small specialist house that also issues Jacques Vallée's journals and a good deal of the field's more serious material. Its involvement places the book on a better list than most treatments of this subject would find.

It should be said that neither author is an art historian, and Dellschau is now principally an art-historical subject. The notebooks are held in major collections, have been exhibited as outsider art, and have a scholarly literature of their own that this book does not fully engage.

Historical Context & Origins

Dellschau's biography is documented and unremarkable. Born in Brandenburg in 1830, he emigrated in 1853, worked as a butcher in Texas, and retired to Houston, where he lived with family and produced the notebooks between roughly 1899 and 1922. He died in 1923.

The material itself is extraordinary and its survival was accidental. The notebooks — thousands of pages of watercolour, collage and coded text, incorporating newspaper clippings Dellschau called 'press blooms' — were discarded after a house fire in the 1960s and rescued from a pile of rubbish. They are now held in major American collections and have been exhibited as significant outsider art.

The claim inside them is specific. Dellschau wrote that in the 1850s a secret society called the Sonora Aero Club, based in the California gold country, built and flew navigable airships powered by a substance he called NB gas, and that its members were sworn to secrecy. He named more than sixty members and gave the craft names like Aero Goosey and Aero Babymyn.

That claim connects to the one genuinely mysterious episode in American aviation history. The airship wave of 1896–97 produced thousands of reports across the United States of a lighted, apparently controlled, navigable craft, years before the Wright brothers — and the Sonora Aero Club story, if true, would supply an answer.

The medical detail Rogerson raises in his review deserves stating because it is documented and relevant. Dellschau's death certificate records arteriosclerosis, a term then used for the dementias, and a late-life flowering of compulsive creative production is a recognised presentation. That does not diminish the work; it does bear on how the coded narrative should be read.

The wider historical setting is also mundane and important. The 1850s and 1860s were a period of intense, well-documented and entirely unsuccessful experimentation with dirigible flight on both sides of the Atlantic, and German-language technical journalism of the period carried a great deal of it. A German-speaking immigrant with an interest in aeronautics had ample real material to elaborate from.

Dellschau's standing today is as an artist. Major institutions hold the notebooks, his work has been shown in significant exhibitions, and the art-historical assessment treats him as a self-taught visionary whose imagined society is the content of the work rather than a claim about the past. That is the mainstream reading and it is not seriously contested.

Core Arguments & Key Concepts

The notebooks are real, coded, and were genuinely decoded. The book's foundational and entirely solid claim. Navarro identified the encryption, worked it out, and reconstructed the narrative. Whatever the narrative means, the decoding is a real piece of documentary work and it is the reason anyone knows what Dellschau wrote.

The Sonora Aero Club narrative is internally elaborate and consistent. More than sixty named members, individual craft with names and specifications, a governing structure, a secrecy oath and a chronology. Internal consistency of that order is what makes the material interesting and it is also exactly what a sustained imaginative project produces.

If the Aero Club existed, the 1896–97 airship wave has an answer. The book's most consequential speculative claim and the reason it belongs in a UFO library at all. A secret American society flying navigable airships decades before powered flight would explain the wave without requiring anything exotic.

The decoder concluded it was imaginary, and that is the book's real finding. Navarro spent decades on this material, had every incentive to find it true, and accepted — reluctantly, as his reviewer put it — that the story was Dellschau's invention. A researcher's conclusion against his own interest is the strongest kind of testimony in this field, and it is the fact a reader should carry away.

There is no external corroboration of any kind. The decisive evidential point. No Sonora Aero Club appears in California records; none of the sixty-plus named members has been independently traced; no craft, component, patent, photograph or contemporary reference exists; and NB gas is not a substance. A secret society of that size operating for years in gold-rush California would have left something.

The book is an assemblage rather than a book, and it shows. Its reviewer put it plainly: not really a proper book at all, more an assemblage of notes and articles, with sections that repeat or contradict one another. That is a fair description of a volume built from one man's decades of accumulated research notes by a second author.

The art-historical reading is the correct one and the book resists it. Dellschau is a major outsider artist whose imagined aviation society is the subject of the work. Treating the notebooks as a historical claim to be adjudicated rather than as a body of visionary art is a category error, and it is the error the book's framing keeps making even as Navarro's own conclusion points the other way.

Key Cases & Evidence Discussed

The notebooks and their recovery. Thousands of pages of watercolour, collage and coded text produced between roughly 1899 and 1922, discarded after a house fire in the 1960s and rescued from rubbish — the survival of the material is itself the first improbable fact in the story.

The cipher and Navarro's decoding. The coded elements embedded in the drawings, the substitution scheme, and the years of work by which Navarro reconstructed the narrative. The book's genuine scholarly content.

The Sonora Aero Club. The claimed 1850s California society of more than sixty named members, its secrecy oath, its internal politics and its dissolution as Dellschau described it.

NB gas. The supposed lifting and motive substance that made the craft possible — a compound with no chemical identity, no analogue and no trace in any technical literature of the period, and the point at which the narrative's physical claims fail outright.

The named airships. Aero Goosey, Aero Babymyn and the rest — individually designed, named and specified craft whose whimsical nomenclature is itself evidence about the nature of the project.

The press blooms. The newspaper clippings Dellschau incorporated into the notebooks, which anchor the work in the aeronautical news of his own period and show what he was reading and elaborating from.

The airship wave of 1896–97. The thousands of American reports of a navigable lighted craft years before powered flight, examined in this site's case file, and the phenomenon the Sonora Aero Club story would explain if any of it were true.

The Aurora, Texas crash claim of 1897. The airship-wave incident with a supposed dead pilot and a marked grave, covered in this site's case file — the other Texas strand of the same episode and, like Dellschau's, a story that does not survive examination.

Critical Reception & Controversies

The book was published by a small specialist house and reviewed in the field's own venues rather than in the general press. The substantial assessment came from Peter Rogerson in Magonia, and it is unusually direct.

Rogerson's verdict was that the Sonora Aero Club is fiction — an imagined society elaborated, he suggested, from bedtime stories Dellschau told his children — and that Dellschau should be understood as an outsider artist creating wonder tales rather than as a witness to a suppressed history. He also noted the death-certificate reference to arteriosclerosis and the recognised association between certain dementias and a late flowering of creative production.

His structural criticism is the one most useful to a prospective reader: this is not really a proper book, more an assemblage of notes and articles, with sections that repeat and occasionally contradict one another. That is what a posthumous-feeling compilation of one researcher's lifetime notes tends to be.

The most important thing in the review, and in the book, is Navarro's own position. Rogerson records that Navarro accepted, with obvious reluctance, that the story was the work of Dellschau's imagination. A researcher who spent decades decoding a document and then concluded against the interpretation he plainly wanted has done something the field very rarely does, and it deserves to be the headline.

The evidential case against the Aero Club has never been seriously contested. No California record of the society exists, none of its named members has been traced, no craft or component survives, no patent or contemporary reference has been found, and its motive substance does not exist. A secret organisation of sixty-plus people building airships over a period of years in a heavily documented gold-rush society would have left a trace.

Where the book has been most criticised by sympathetic readers is in refusing to follow its own evidence. Having presented Navarro's decoding and Navarro's conclusion, the framing continues to entertain the possibility that the Aero Club was real, and a reader who does not attend carefully will come away with the opposite impression from the one the decoder reached.

The fair placement is that this is the indispensable source on a genuinely extraordinary body of material, written badly, arguing weakly, and containing an honest and important finding that its own presentation obscures.

Influence & Legacy

The book preserved Navarro's work, and that is a real service. Decades of amateur decoding on unique material would otherwise have existed only in one man's files, and the reconstruction of the Sonora Aero Club narrative is now on the public record because Crenshaw assembled it.

It also brought the notebooks to an audience that would not have found them through the art world. Dellschau's principal reception is now art-historical — major collections, significant exhibitions, a scholarly literature treating him as an important self-taught visionary — and this book is how a substantial number of readers in the anomalies field first encountered him.

Its contribution to the airship-wave question is negative and useful. The Sonora Aero Club was the most specific candidate explanation the 1896–97 wave has ever had, and establishing that it does not survive examination narrows the field. This site's airship wave case file is better off for the elimination.

The cautionary legacy is about coherence as evidence. Dellschau's narrative is internally consistent, richly detailed, sustained over two decades and populated by sixty named individuals — and it is invented. Elaborate internal consistency is what sustained imaginative work produces, not what corroboration produces, and confusing the two is one of the most common errors in this literature. Navarro, to his great credit, did not make it.

The Book

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